Merge pull request #111 from whymarrh/develop

Update contribution guidelines
Ignore CSS source maps
Update Zend Framework and PHPUnit versions
Whitespace and docblocks cleanup
Merge upstream develop into develop
Remove develop brancn build status
Add linkt to GitHub Guides
Add link to JSHint
Fix link to contributing document
Small grammar fix
Add link to PHPUnit website
Created GitHub module - a wrapper for their API.

Created a new GitHub module which acts as a wrapper around GitHub's v3 API.

Plans for the wrapper currently only include the ability to sort contributors
by something other than their contributions.
Sort contributors by username.
Avatar view helper.
Added README file.
Updated README and view helper.
Display the list of contributors on the about page.

The list of contributors to the ABA Lookup repository on GitHub are
displayed on the about page. Added two `img-src` rules to the CSP
to allow the avatars to be displayed.
Fixed failing tests.

Apparently the working directory was causing issues with the loading
of the configurations in the GitHub API module. That's fixed now.
Update Content-Security-Policy for GitHub avatars