Start java app dev

First commit to github of the Java code intended for BeagleBoneBlack.

Several major changes. The cheap usb rfid readers (~$10) act as keyboard
input. so this is a console app. Serial reader capability may be added
later if necessary.

It can currently hit the server and get auth y/n and time, then run the
countdown timer. No HW specific code has been written. There are
placeholders for relay on/off functionality and current sensor readings,
but the structure should not change significantly.

Settings can be modified in RFID_Settings.cfg without rebuilding the
app. This file may need to be moved to src/ folder depending on your
environment.