Added a block-out GUI (EnigmaGUI.java), a background image, and a main
class to run it as an application (Enigma.java). Block-out GUI is still
a work in progress. 

Plug Board functionality is not fully implemented. 
File import is not fully implemented. I dropped in the code from
TestDriver.java to give the visual impression.
Error checking is not in place. 
GUI will not protect against invalid setting combinations or detect
invalid input. 
GUI currently using string encryption functionality only. 
Lightboard is not functional. (purely placeholder at this time.)

Code Review: Tips would be appreciated.

QA Testing: Machine output with valid Rotor setting, Ring setting,
Position setting, Reflector setting, and Text box input should be
functional. Press Encrypt to encrypt as a string.