Adds new testing libraries.
Removes unused .gitkeep file.
Fixes an [issue](https://github.com/inventit/processing-android-serial/issues/1) where [Arduino Due](http://arduino.cc/en/Main/arduinoBoardDue) cannot be detected by [usb-serial-for-android](https://code.google.com/p/usb-serial-for-android/) library.

Now all Arduino devices are accepted (but not sure they all work properly. [Give us your feedback](https://github.com/inventit/processing-android-serial/issues))
Merge branch 'feature/additional_usb_filter_support' into develop
0.0.2-alpha : June 20, 2013
 * Fixes an [issue](https://github.com/inventit/processing-android-serial/issues/1) where [Arduino Due](http://arduino.cc/en/Main/arduinoBoardDue) cannot be detected by [usb-serial-for-android](https://code.google.com/p/usb-serial-for-android/) library. Now all Arduino devices are accepted (but not sure they all work properly. [Give us your feedback](https://github.com/inventit/processing-android-serial/issues))
 * Adds unit testing libraries, [Robolectric](https://github.com/robolectric/robolectric/) and [Mockito](https://code.google.com/p/mockito/)
 * The release binary has been moved to [our SourceForge project page](https://sourceforge.net/projects/procandser/)
Fixes an issue where junit library is missing in the project file.
Removes unused class path setting.
Merge branch 'release/0.0.2-alpha' into develop