CCD-Fix Alpha CB on Show & Add PIL PickFromScreen

Alpha Checkbox was working backwards on Showing. Fixed.

NEW!
Also Added PIL Pick Color From Screen Button To fill a gap in the grid
sizer.
Could use a bit more work and tweaking with the imports.
TODO: Need to add a global as to whether PIL/imports succeeded and work
in the showing of the button otion & move imports to top of file and
document properly.