Fixed Bug, Added More Functionality

Fixed a resource leak where audio streams weren't being closed when the
user was finished with it. Added a test button for testing purposes.
Rearranged the order of how the Encryption process will run. Now the
copied WAV file has no communication with the original WAV file after
the initial copy. Before the original WAV file was going to perform the
encrypting and then pass that data to the copied WAV file.
Fixed Bugs, Added New/Altered Old Functions

Fixed a bug where the Open/Close File dialogue windows would allow the
user to change the viewed file types from only WAV files to any type of
file. Now the user can only select WAV files. Added the validation
function isUsingAudioResources, and the function releaseAudioResources
to fix a resource leak bug. Created the readWavFileData function to
specifically read the data from a WAV file. Altered the saveFile
function to be copyWavFile function, and gave it code to point the JWav
to the copied WAV file in preparation for injecting the hidden message.
Added the ability to inject data into an existing WAV file via the
injectEncryptedMessage() function. Lastly, added a testing function to
test whatever needs testing.