Drogue parachute mach lock based on MPU's accelerometer

[juan00juan0]

I added Mach immunity using the MPU's accelerometer. The vertical velocity is calculated using the y-axis acceleration data. In order for the drogue parachute to deploy, this velocity must be less than than SUBSONIC_SPEED (which has been defined under setup_params.h).

• The loopTimer variable measures the main loop's time interval.
• loopTimer is reset on every loop cycle
• The TimeData struct stores the value of this time interval in the dt member.
• avg_y_accel stores the average y-axis acceleration based on the 3 most recent Samples.
• mpuVelY is the vertical velocity based on the integration of avg_y_accel
• Added the conditional statement mpuVelY < SUBSONIC_SPEED to avoid deployment of the drogue parachute if the vertical velocity is too high ( and possibly in the transonic range)

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