add IMU bootstrap params

yaml/processor_imu.yaml

 time_tolerance: 0.0025         # Time tolerance for joining KFs (half of 5ms or 200Hz)
 unmeasured_perturbation_std: 0.000001
 apply_loss_function: false
+
 keyframe_vote:
     voting_active:      false
     max_time_span:      1.0   # seconds
     max_buff_length:    500   # motion deltas
     dist_traveled:      2.0   # meters
     angle_turned:       0.1   # radians (1 rad approx 57 deg, approx 60 deg)
+
+bootstrap:
+    enable: false 
+    method: "G"             # methods: "G", "STATIC" or "V0_G"
+    averaging_length: 0.10  # seconds
+    keyframe_provider_processor_name: "processor_other_name" # Not yet implemented
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