travis-ci: Update build

* Whitelist branch && update deps

* Run device_info so we can get some diagnostic output...

* Fix directory path of OSX v10.7 SDK

* Disable brew install of cmake & exec of font_cache test

* Update third-party deps URL (libRocket)

* Add freetype2 build dep (libRocket)

* Exec libRocketTest
libRocketTest: Add additional search paths
Fix compile err affecting Xcode generated project builds
Use default OSX SDK path