disable more stuff for quick build debug.
fix missing sensitivity lines and prevent keymap data cs line
latching.
add missing sensitivity.
convert matrix from array to vector and simplify related
logic.
substantial refactor to work around ISE tool crashes and other
problems.  Seems that the Xess SD card modules and my code
don't like each other or something.  Will go to using Steven
Merrifield's code, and simplify things greatly.  Issue #24.