0.3.0

Bugfix and Improvements:

- Fixed get firmware command
- Improved bluetooth connection class such that the bluegiga dongle does not be to be connected when the class is created
- Added the flush command for the Connection class
- Updated the example program to have the get firmware/hardware version command, get battery level command, and connect to either a TappyBLE or TappyUSB
- Added a method to convert the UID byte array to a string for the Tag class