Removed Unnecessary Try/Catch Statements

For the WavHeader, WavFormatChunk, and WavDataChunk classes, I removed
the try/catch statements. This was done so that the
Audio_Steganography_Driver would catch the Exceptions and decide what to
do from there which is more appropriate.
Refactored GUI and Added Validation Code

The GUI is now more user friendly and pleasing to the eye. Added
validation code for "goButton", "playButton", and "stopButton" so that
they are only enabled when the necessary input is given. Added a reset
button as well that resets the whole form. Added a new class
"MyDocumentListener" that helps in validating the password and message
fields.