Update README, karma.conf.js, and fix `gulp watch` ( #848 )

[DLvalentine]

• Commit package-lock.json
• README: Reflects minimum Node version, mentions NVM
• README: Uses npm run commands instead of node commands now
• karma.conf.js: Use ChromeHeadless instead of PhantomJS as browser for tests, PhantomJS was no longer working
• webpack.config.js: Make TODO note in webpack config about noisy file generation that could be ignored
• package.json: Started working on dependency upgrades/fixes, starting with graceful-fs. It was preventing gulp watch from working.
• package.json: Included myself as contributor

[DLvalentine]

Ah, I meant to commit package-lock.json since that's a good practice, but it looks like it got blown away. No biggie, would just need to either add that or amend the commit message.

[DLvalentine]

Converted to a draft, think I overlooked something, there's a dependency conflict in this commit that I need to resolve

[joemccann]

sounds good thanks!