* Clarify the license for files we have signoff on
* Update against the currently signed off files
* Remove unused and not clearly licensed headers
* Replace an #endif I accidentally removed while resolving merge conflicts
The previous two options were COL2ROW, ROW2COL; this adds CUSTOM_MATRIX
to disable the built-in matrix scanning code.
Most notably, this obviates the need to set MATRIX_ROW_PINS or
MATRIX_COL_PINS.
Fix memory leaks by using stack instead of malloc
Reduce memory usage by having less temporary bufffers
Remove warnings by adding includes
Decrease code size by 608 bytes (mostly due to not linking malloc)
More robust handling of buffer overflows