msg ROS2 compatibility, microdds_client improvements (timesync, reduced code size, added topics, etc), fastrtps purge

- update all msgs to be directly compatible with ROS2
 - microdds_client improvements
   - timesync
   - reduced code size
   - add to most default builds if we can afford it
   - lots of other little changes
 - purge fastrtps (I tried to save this multiple times, but kept hitting roadblocks)

msg/HeaterStatus.msg

@@ -0,0 +1,20 @@
+uint64 timestamp	# time since system start (microseconds)
+
+uint32 device_id
+
+bool heater_on
+bool temperature_target_met
+
+float32 temperature_sensor
+float32 temperature_target
+
+uint32 controller_period_usec
+uint32 controller_time_on_usec
+
+float32 proportional_value
+float32 integrator_value
+float32 feed_forward_value
+
+uint8 MODE_GPIO  = 1
+uint8 MODE_PX4IO = 2
+uint8 mode