Added initial example web API client and tests.

Summary:
Added a simple OAuth1.0a client that can fetch a list of topics and tests containing a self-contained Jersey Oauth1.0a server to test authentication.

The project can be seen hosted at [GitHub](https://github.com/MediaMiser/rest-client).

Test Plan:
Automated testing:
* [Unit tests](https://travis-ci.org/MediaMiser/rest-client/)
* [Coverage](https://coveralls.io/r/MediaMiser/rest-client/)

Reviewers: samer.albuhaisi, yan.shi, david.nadeau, fan.zhao

Reviewed By: yan.shi

Differential Revision: http://phabricator.mediamiser.internal/D1030