Boot Bravo board for Hamvention 2013.

* Moved signalgenerator.py to 10-bit DAC w/ tests.
* Correctly aligned GPIO pins given the Libero smart design settings.
* ADC power management.
* CMX991 register file API for app & unit tests.
* CMX991 PLL control functions.
* CMX991 power management.
* Blink LED utility program.