Reduce NPM package size by adding more files to .npmignore list

[fershad]

This PR looks to reduce the size of the @tgwf/co2 NPM package by adding code and files that are not necessary for external/production users to the .npmignore file.

The changes made are reflect those raised in #121. Namely:

• Remove the IIFE code from the package that is shipped to NPM. Instead, commit this code to git for anyone who needs to use it.
• Ignore dotfiles that are related to development.
• Ignore all data files except those present in the dist/cjs and dist/esm folders. These data files are not consumed anywhere else in the code. Someone who's installing this library from NPM would access grid intensity data using the methods outlined here: https://developers.thegreenwebfoundation.org/co2js/data/#using-emissions-intensity-data
• Ignore the src folder. A bit controversial, but all the code can be found on GitHub. dist/cjs and dist/esm folders also ship with source maps for anyone needing to get into the code to debug.

In all, this reduces the files shipped by 41 & total package size by ~280 kB. The below diff shows the results of running the npm pack --dry-run command before and after the changes are applied. Files which have been removed from the package are highlighted.

- npm notice 3.6kB   .all-contributorsrc                                
- npm notice 225B    .esbuild.browser.js                                
- npm notice 941B    .esbuild.esm.js                                    
- npm notice 376B    .esbuild.node.js                                   
- npm notice 8B      .eslintignore                                      
- npm notice 183B    .gitpod.yml                                        
  npm notice 9.1kB   CHANGELOG.md                                       
  npm notice 12.0kB  LICENSE                                            
  npm notice 562B    NOTICE                                             
  npm notice 12.5kB  README.md                                          
- npm notice 3.4kB   data/output/average-intensities.js                 
- npm notice 32.3kB  data/output/average-intensities.json               
- npm notice 3.4kB   data/output/marginal-intensities-2021.js           
- npm notice 104.6kB data/output/marginal-intensities-2021.json         
  npm notice 1.9kB   dist/cjs/1byte.js                                  
  npm notice 3.4kB   dist/cjs/1byte.js.map                              
  npm notice 8.8kB   dist/cjs/co2.js                                    
  npm notice 14.9kB  dist/cjs/co2.js.map                                
  npm notice 1.0kB   dist/cjs/constants/file-size.js                    
  npm notice 306B    dist/cjs/constants/file-size.js.map                
  npm notice 2.4kB   dist/cjs/constants/index.js                        
  npm notice 1.8kB   dist/cjs/constants/index.js.map                    
  npm notice 4.5kB   dist/cjs/data/average-intensities.min.js           
  npm notice 5.9kB   dist/cjs/data/average-intensities.min.js.map       
  npm notice 4.6kB   dist/cjs/data/marginal-intensities-2021.min.js     
  npm notice 6.5kB   dist/cjs/data/marginal-intensities-2021.min.js.map 
  npm notice 7.9kB   dist/cjs/helpers/index.js                          
  npm notice 10.2kB  dist/cjs/helpers/index.js.map                      
  npm notice 2.0kB   dist/cjs/hosting-api.js                            
  npm notice 2.8kB   dist/cjs/hosting-api.js.map                        
  npm notice 2.6kB   dist/cjs/hosting-json.node.js                      
  npm notice 4.7kB   dist/cjs/hosting-json.node.js.map                  
  npm notice 3.0kB   dist/cjs/hosting-node.js                           
  npm notice 4.6kB   dist/cjs/hosting-node.js.map                       
  npm notice 1.5kB   dist/cjs/hosting.js                                
  npm notice 706B    dist/cjs/hosting.js.map                            
  npm notice 1.8kB   dist/cjs/index-node.js                             
  npm notice 514B    dist/cjs/index-node.js.map                         
  npm notice 2.0kB   dist/cjs/index.js                                  
  npm notice 629B    dist/cjs/index.js.map                              
  npm notice 27B     dist/cjs/package.json                              
  npm notice 7.9kB   dist/cjs/sustainable-web-design.js                 
  npm notice 15.5kB  dist/cjs/sustainable-web-design.js.map             
- npm notice 61B     dist/data/functions/generate_average_co2.d.ts      
- npm notice 151B    dist/data/functions/generate_average_co2.d.ts.map  
- npm notice 62B     dist/data/functions/generate_marginal_co2.d.ts     
- npm notice 153B    dist/data/functions/generate_marginal_co2.d.ts.map 
- npm notice 4.0kB   dist/data/output/average-intensities.d.ts          
- npm notice 395B    dist/data/output/average-intensities.d.ts.map      
- npm notice 4.3kB   dist/data/output/marginal-intensities-2021.d.ts    
- npm notice 431B    dist/data/output/marginal-intensities-2021.d.ts.map
- npm notice 134B    dist/data/utils/getCountryCodes.d.ts               
- npm notice 148B    dist/data/utils/getCountryCodes.d.ts.map           
- npm notice 105B    dist/data/utils/mapCountries.d.ts                  
- npm notice 143B    dist/data/utils/mapCountries.d.ts.map              
- npm notice 330B    dist/data/utils/parseCSVRow.d.ts                   
- npm notice 164B    dist/data/utils/parseCSVRow.d.ts.map               
  npm notice 1.0kB   dist/esm/1byte.js                                  
  npm notice 7.5kB   dist/esm/co2.js                                    
  npm notice 117B    dist/esm/constants/file-size.js                    
  npm notice 797B    dist/esm/constants/index.js                        
  npm notice 3.5kB   dist/esm/data/average-intensities.min.js           
  npm notice 3.5kB   dist/esm/data/marginal-intensities-2021.min.js     
  npm notice 6.8kB   dist/esm/helpers/index.js                          
  npm notice 1.1kB   dist/esm/hosting-api.js                            
  npm notice 195B    dist/esm/hosting.js                                
  npm notice 372B    dist/esm/index.js                                  
  npm notice 25B     dist/esm/package.json                              
  npm notice 7.6kB   dist/esm/sustainable-web-design.js                 
- npm notice 15.9kB  dist/iife/index.js                                 
- npm notice 58.2kB  dist/iife/index.js.map                             
- npm notice 365B    fixup                                              
  npm notice 29B     index.d.ts                                         
  npm notice 2.3kB   package.json                                       
- npm notice 2.6kB   src/1byte.js                                       
- npm notice 10.7kB  src/co2.js                                         
- npm notice 70B     src/constants/file-size.js                         
- npm notice 1.3kB   src/constants/index.js                             
- npm notice 2.9kB   src/data/average-intensities.min.js                
- npm notice 3.0kB   src/data/marginal-intensities-2021.min.js          
- npm notice 7.0kB   src/helpers/index.js                               
- npm notice 1.9kB   src/hosting-api.js                                 
- npm notice 3.2kB   src/hosting-json.node.js                           
- npm notice 3.3kB   src/hosting-node.js                                
- npm notice 431B    src/hosting.js                                     
- npm notice 270B    src/index-node.js                                  
- npm notice 336B    src/index.js                                       
- npm notice 11.6kB  src/sustainable-web-design.js                      

- npm notice package size:  89.1 kB                                 
- npm notice unpacked size: 476.2 kB                                
- npm notice shasum:        4f516cc4d9048fe601ec715f21d6ad1d94296a4b
- npm notice integrity:     sha512-iQZMYdLP+l1Ky[...]kgbB/x3Gc/cQA==
- npm notice total files:   88                                      
---
+ npm notice package size:  40.5 kB                                 
+ npm notice unpacked size: 193.4 kB                                
+ npm notice shasum:        6300baa566d61730d0758aad412e44157c7ba366
+ npm notice integrity:     sha512-F6JOR2yWn6uUH[...]ibQqNv7mUZg9w==
+ npm notice total files:   47                                      

[mrchrisadams]

:shipit: @fershad