Move to using OAuth and tokens

[tamagokun]

User creates a build URL by providing their repo URL, any configuration options. That request takes them to OAuth for Github or Bitbucket, etc, and gets a token. Token can be used to clone repo and perform build.

1. POST /deployments {repo: 'github.com/ripeworks/mysite.git'}
2. Please visit this URL: https://oauth.github.com/authorize?code=xxxxxxxxxxx
3. redirect back to deployment with token
4. {deployment: 'https://jekyllbuild.com/1odkcoz0'}

Any POST sent to the final URL will trigger a build.

https://blog.github.com/2012-09-21-easier-builds-and-deployments-using-git-over-https-and-oauth/