Add Navball Mode feature

Author: CodapopKSP

src/Helpers.cpp

@@ -42,3 +42,9 @@ void KerbalSimpit::setCameraMode(byte mode)
 {
   _send(CAMERA_CONTROL_MODE, &mode, 1);
 }
+
+void KerbalSimpit::cycleNavBallMode()
+{
+  byte payload = 0;
+  _send(NAVBALLMODE_MESSAGE, &payload, 1);
+}

src/KerbalSimpit.h

@@ -133,6 +133,8 @@ class KerbalSimpit
 
   void setCameraMode(byte mode);
 
+  void cycleNavBallMode();
+
   void printToKSP(String msg);
   void printToKSP(String msg, byte options);
 

src/KerbalSimpitMessageTypes.h

@@ -270,6 +270,8 @@ enum InboundPackets
     KEYBOARD_EMULATOR = 26,
 	/** Send a message to control the custom axis. */
     CUSTOM_AXIS_MESSAGE = 27,
+    /** Send a message to cycle the NavBall mode to the next mode. */
+    NAVBALLMODE_MESSAGE = 28,
 };
 
 /** Action Group Indexes