Auto-update contributors list

Forgive my ignorance, but I’m not sure the contributors file needs to be static/manually updated. This seemed to work on my local copy.
Merge pull request #38 from OliverJAsh/gh-pages

Add title to Checklist page SEO++
Merge pull request #39 from daneden/patch-1

Auto-update contributors list
Update README.md

Clarifying rake server.
Use callback parameter for contributors JSON url

This should help resolve CORS issues
Add Gemfile
Merge pull request #41 from thomassjogren/patch-2

Update README.md
Further description for local server directions
Merge pull request #44 from OliverJAsh/feature/gemfile

Add Gemfile
Merge pull request #43 from daneden/patch-1

Use callback parameter for contributors JSON url (resolves #39)
Rename tldr to description, fixes #37