update .gitignore
adding a LICENSE file
adding README.md
adding a supporting compiler.h
A first attempt at configuring USART for console output.

Doesn't work yet.
enable extra warnings.
got USART1 to work
renaming usart_port typedef
renaming DISCOVERY_USART2 as CONSOLE_USART
minor rename in a function signature
remove RX related definitions; switching more to USART1
renaming a variable
console output seems to be working now
fix a bug in puts()
printf() works!
printf() works!
changing default console baud to 115200