Stubbed out a basic idea for sound control, utilising a global
preference class. Need to figure out algorithm for converting a
percentage to a reasonable decibel gain/loss.
Finished graphics for sound and music controls, as well are preliminary
sound dialog skeleton. Okay button drawn incorrectly, screen size not
accounting for titlebar, and of course the volume slider needs to be
actually implemented to test the percentage-to-decibel algorithm.
Fixed some display issues in SoundControlDialog. Swapped 'Sound' and
'Music' icons as I originally got them backwards.
Fixed resource leak with WorldResource never being disposed

Adding a working demo sound to sound controls; currently requires
tweaking to get the sound to easily flow from nothing to loud smoothly.
Finally got sound system working mostly nice, although more tweaking may
be needed in the future. When sound is turned to 0 sounds don't play
(including music) making it possible to finally shut off the music and
listen to iTunes (if desired)

Still need to skin the slider to look like the Monkey Shines volume
slider and not some out-of-place Java-style slider.
Sound controls appear to finally be skinned properly.

Fixes #3
Updated .jar