Fix preprocessor directive spelling
Macros for various Tiva processors
Port mapping for various launchpads
Rearrange conditionals - test for tiva first,
in case other platforms than AVR can use the AVR code (e.g. Due?)
Include rom_map.h
Port defines for different launchpads
Data port mask - constant for AVR
Dynamic define refresh.  Move TIVA detect to header.
DATAPORTBASE
Rowtime calculation - adjust timer resolution
Demo code - more AVR PROGMEM fixes