Add Gemfile with dependencies on `github-pages` gem.
Add more details about setting up a local devel environment and license details to README.md
`bundle` command is not installed by default, however the `gem` command is with Ruby v1.9.3 and newer.
Update title to match previous commit.
Add Gemfile.lock to ensure developers are running the same version, even if GitHub ignores the file when 'deploying' GitHub Pages.
Merge pull request #13 from lantins/add-gemfile-and-update-devel-help

Add gemfile and update devel help #wtwtch