Add path api

Fix

msg/CMakeLists.txt

@@ -108,7 +108,7 @@ set(msg_files
 	GimbalManagerSetAttitude.msg
 	GimbalManagerSetManualControl.msg
 	GimbalManagerStatus.msg
-	GlobalTrajectorySetpoint.msg
+	GlobalPathSetpoint.msg
 	GpioConfig.msg
 	GpioIn.msg
 	GpioOut.msg

msg/GlobalPathSetpoint.msg

@@ -1,5 +1,5 @@
-# Trajectory setpoint in NED frame
-# Input to PID position controller.
+# Path setpoint in NED frame
+# Input to Guidance controller
 # Needs to be kinematically consistent and feasible for smooth flight.
 # setting a value to NaN means the state should not be controlled
 
@@ -11,6 +11,6 @@ float64 lat			# Latitude, (degrees)
 float64 lon			# Longitude, (degrees)
 float32 alt			# Altitude AMSL, (meters)
 # NED local world frame
-float32[3] velocity # in meters/second
-float32[3] acceleration # in meters/second^2
-float32[3] jerk # in meters/second^3 (for logging only)
+float32[3] tangent # Unit vector tangent to path
+float height_rate
+float32 curvature