STM32 Discovery testing

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Just me playing with different peripherals that came on a stm32f4 Discovery board Hopefully it'll eventually become a working quadcopter

######So far i have working:

1. PWM (TIM4 4 channels)
2. I2C
3. SPI
4. TIM3 with Interrupt
5. L3GD20(Gyroscope)
6. LSM303DLH (Accelerometer and Magnetometer)
7. Push button with a Interrupt
8. Systick Timer