STM32F30x - Add support for I2C2.
STM32F30x - Add support for UART3 - untested.
Whitespace cleanup.
Add MPU9150 driver.

This is a almost a complete clone of the 6050 - needs cleanup and
de-duplication.
Support the Sparky board by peabody124 - work in progress, not flight
ready.

https://github.com/TauLabs/TauLabs/wiki/Sparky

http://buildandcrash.blogspot.co.uk/2013/05/sparky-testing-and-building-no-crashing.html
Fix comments in system startup files.
STM32F30x - Fix uart3 pinsource definitions

UART3 RX/TX working on sparky.
STM32F30x - Allow overriding of USARTx GPIO pins from target.h.

USART1 RX/TX now working on Sparky.
SPARKY - Update UART2 configuration.

UART2 RX working using SumD.
STM32F30x - Fix GPIO initialisation.

Closes #154
SPARKY - Use RX_PPM by default.
SPARKY - PWM output on PWM1-10.
SPARKY - Adding documentation.
SPARKY - Adding note regarding the TauLabs bootloader.