18F/myusa — pull request #397 by polastre (2014-10-07 00:13:23+00:00)
Title: Implement and provide docs for the MyUSA login button

Similar to other OAuth providers, give guidelines for how to use the MyUSA button.

Store the CSS for safe keeping in case we need to update it on AWS.

Note that `api.md` and `_developer.html.erb` are auto-generated files; ignore their diffs and focus instead on the source `.md` files.