Set default altitude and speed override

Set default altitude override to 30 meters above ground.
Set default airspeed to 17 meters per second.

mavsdk_wrapper.cpp

@@ -52,7 +52,7 @@ static Coordinates targeted_destination;
 static float targeted_radius = DEFAULT_RADIUS;
 static Coordinates projected_destination;
 
-static const float DEFAULT_SPEED = 16;
+static const float DEFAULT_SPEED = 17;
 static float last_override_altitude;
 static float last_override_speed;
 
@@ -302,7 +302,7 @@ int start(const char * ip, int port, const char * log_file, int timeout) {
     } while(isnan(abs_altitude) || abs_altitude == 0);
 
     origin = telemetry->position();
-    last_override_altitude = origin.absolute_altitude_m;
+    last_override_altitude = origin.absolute_altitude_m + DEFAULT_OVERRIDE_ALTITUDE;
     last_override_speed = DEFAULT_SPEED;
 
     log("MAVSDK started...");