Re-licensed the AB2 Technologies msp430 software

Moved from GPL to Apache licensing to allow more permissive sharing of
our content. Going forward, all new files will be Apache licensed as
well.
clock.h: include config fix

Removed the unnecessary dependency of a project-specific main.h.
Added the completed f5510 pin framework

The pin framework allows pins to be treated more like objects, and helps
to more consistently and appropriately abstract low-level pin register
operations. This infrastructure helps to minimize the amount of
configuration that is done using header files as it provides runtime
derivation of all port registers.