Bootstrap unity_autopilot_wrapper:

 - Moved cmake macros to detect GTest and Xorg-GTest to their own files
 - New matcher to match display numbers
 - New mock and interface for X11 Connections
 - Bootstrap acceptance tests for the Autopilot test fixture
 - Unit tests for display detection and server setup
 - Provide an ::testing::Environment for clients to use in order
   to start a server, dbus and compiz
 - Provide a sample that uses this environment to run all the autopilot
   tests in Xephyr
 - Update .travis.yml