Assortment of minor goodies
Created by: sonninnos
Prevented 2nd fire button from firing if RetroPad A is mapped to a key.
Made a minimal correction to uncropped NTSC geometry. Normally it is set at 480/240px, and that is where statusbar will be drawn, but UAE does not output NTSC quite that far, making the statusbar not clearing properly.
Also updated and corrected readme again (removed dead links and made reading easier).