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-posix/1030_plane

@@ -37,7 +37,6 @@ then
 
 	param set RWTO_TKOFF 1
 
-	param set WEST_EN 1
 fi
 
 set MIXER_FILE etc/mixers-sitl/plane_sitl.main.mix

ROMFS/px4fmu_common/init.d-posix/1040_standard_vtol

@@ -38,7 +38,6 @@ then
 	param set VT_MOT_COUNT 4
 	param set VT_TYPE 2
 
-	param set WEST_EN 1
 fi
 
 set MAV_TYPE 22

ROMFS/px4fmu_common/init.d-posix/1041_tailsitter

@@ -38,7 +38,6 @@ then
 	param set VT_MOT_COUNT 0
 	param set VT_TYPE 0
 
-	param set WEST_EN 1
 fi
 
 set MAV_TYPE 20

ROMFS/px4fmu_common/init.d-posix/1042_tiltrotor

@@ -41,7 +41,6 @@ then
 	param set VT_ELEV_MC_LOCK 0
 	param set VT_TYPE 1
 
-	param set WEST_EN 1
 fi
 
 set MAV_TYPE 21

ROMFS/px4fmu_common/init.d-posix/rcS

@@ -164,7 +164,6 @@ then
 
 	param set TRIG_INTERFACE 3
 
-	param set WEST_EN 0
 fi
 
 # Adapt timeout parameters if simulation runs faster or slower than realtime.
@@ -213,10 +212,6 @@ sensors start
 commander start
 navigator start
 
-if param compare WEST_EN 1
-then
-	wind_estimator start
-fi
 
 if ! param compare MNT_MODE_IN -1
 then

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.
 	#