Airspeed Selector: repurpose wind estimator into an airspeed (selection, validation) module.

This new airspeed module does:
  -runns an airspeed validator for every airspeed sensor present, which checks measurement validity and estimates an airspeed scale
  -selects another airspeed sensor if for the current one a failure is detected
  -estimates airspeed with groundspeed-windspeed if no valid airspeed sensor is present
  -outputs airspeed_validated topic

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>

ROMFS/px4fmu_common/init.d/rc.fw_apps

@@ -15,9 +15,8 @@ ekf2 start
 #
 fw_att_control start
 fw_pos_control_l1 start
-
+airspeed_selector start
 #
 # Start Land Detector.
 #
 land_detector start fixedwing
-

ROMFS/px4fmu_common/init.d/rc.vtol_apps

@@ -21,10 +21,10 @@ mc_att_control start
 mc_pos_control start
 fw_att_control start
 fw_pos_control_l1 start
+airspeed_selector start
 
 #
 # Start Land Detector
 # Multicopter for now until we have something for VTOL
 #
 land_detector start vtol
-

ROMFS/px4fmu_common/init.d/rcS

@@ -435,14 +435,6 @@ else
 	#
 	navigator start
 
-	#
-	# Start the standalone wind estimator.
-	#
-	if param compare WEST_EN 1
-	then
-		wind_estimator start
-	fi
-
 	#
 	# Start a thermal calibration if required.
 	#