OpticalFlow: add optical flow velocity logging

This is important to align the flow with the IMU data and verify that
the compensation is properly done

msg/CMakeLists.txt

@@ -56,6 +56,7 @@ set(msg_files
 	esc_report.msg
 	esc_status.msg
 	estimator_innovations.msg
+	estimator_optical_flow_vel.msg
 	estimator_sensor_bias.msg
 	estimator_states.msg
 	estimator_status.msg

msg/estimator_optical_flow_vel.msg

@@ -0,0 +1,8 @@
+uint64 timestamp			# time since system start (microseconds)
+uint64 timestamp_sample			# the timestamp of the raw data (microseconds)
+
+float32[2] vel_body			# velocity obtained from gyro-compensated and distance-scaled optical flow raw measurements in body frame(m/s)
+float32[2] vel_ne			# same as vel_body but in local frame (m/s)
+float32[2] flow_uncompensated_integral	# integrated optical flow measurement (rad)
+float32[2] flow_compensated_integral	# integrated optical flow measurement compensated for angular motion (rad)
+float32[3] gyro_rate_integral		# gyro measurement integrated to flow rate and synchronized with flow measurements (rad)

msg/tools/uorb_rtps_message_ids.yaml

@@ -285,6 +285,8 @@ rtps:
     id: 136
   - msg: navigator_mission_item
     id: 137
+  - msg: estimator_optical_flow_vel
+    id: 138
   ########## multi topics: begin ##########
   - msg: actuator_controls_0
     id: 150