unmanned ground vehicle (UGV) controllers and Traxxas Stampede configuration (#7175)

ROMFS/px4fmu_common/init.d/rc.gnd_defaults

@@ -0,0 +1,32 @@
+#!nsh
+
+set VEHICLE_TYPE ugv
+
+if [ $AUTOCNF == yes ]
+then
+#
+# Default parameters for UGVs
+#
+	param set NAV_DLL_ACT 0
+	param set NAV_ACC_RAD 2.0
+	
+	# temporary
+	param set NAV_FW_ALT_RAD 1000
+
+	param set MIS_LTRMIN_ALT 0.01
+	param set MIS_TAKEOFF_ALT 0.01
+fi
+
+# Enable servo output on pins 3 and 4 (steering and thrust)
+# but also include 1+2 as they form together one output group
+# and need to be set together.
+set PWM_OUT 1234
+
+# PWM Hz - 50 Hz is the normal rate in RC cars, higher rates
+# may damage analog servos.
+set PWM_RATE 50
+
+# This is the gimbal pass mixer
+set MIXER_AUX pass
+set PWM_AUX_RATE 50
+set PWM_AUX_OUT 1234