Add docs

[chrisdmacrae]

Need to add docs to the project:

• Quick start
• Installation
• Basic usage
  • Choosing a starter
  • Running the server
  • Building assets
  • Open a local copy of the documentation
• Creating pages
  • Static html
  • Nunjucks html
  • Nunjucks extends
  • Nunjucks partials
  • Frontend nunjucks
• Writing css
• Writing Javascript
• Add data to pages
  • Front matter
  • Local data files
  • Global data files
• Passing data between pages
  • Query params
  • Form submit
  • Javascript post
• Creating routes & redirects
  • Redirects
  • Branching
  • Passing additional data
• Managing sessions
  • Adding default session data
  • Adding custom data
  • Resetting session data
  • Managing multiple users
• Publishing on the web
  • Using authentication
  • Using zeit.now
  • Using heroku
• Updating
  • Updating the local kit
  • Updating the cli
  • Updating your starter