Record, but don't use, estimator state.

Record estimator state but use measurements and calculated lean angle,
steer rate as input to LQR controller.
Record rear wheel rate PI controller states.
Add filename to plot titles.
Use average of 100 samples for initial lean angle.

Set the lean angle to be the average of 100 samples (0.5 sec) of static
(acceleration) lean angle before using gyroscope integration for lean
calculation.
Add new message type to record integrated gyro lean.
Turn on both LEDs during startup sequence.

Both LEDs turn on while average static lean is calculated. Afterwards,
each LED will turn on if steer, lean is within range.
Minor formatting fix.
Code refactor.

Move lean angle calculation from ForkMotorController to ControlLoop.
Merge remote-tracking branch 'oliverlee/fullorderobs' into full_order_observer

Conflicts:
	firmware/src/rear_motor_controller.cpp

Comment out logging of problematic integral control parameters/states. Only
proportional control is used.