fix #249: report battery levels even if no GPS lock

@professr I noticed you added a "newStatus" observable to the GPS class.
Do you remember why you didn't remove the old GPS status (which seemed
to be dumber).  Is it just because you didn't want to risk breaking
MeshService?  (I assume) In this change I removed the old Observable
and all seems well (just using newStatus everywhere).

src/mesh/MeshService.h

@@ -4,6 +4,7 @@
 #include <assert.h>
 #include <string>
 
+#include "GPSStatus.h"
 #include "MemoryPool.h"
 #include "MeshRadio.h"
 #include "MeshTypes.h"
@@ -17,7 +18,8 @@
  */
 class MeshService
 {
-    CallbackObserver<MeshService, void *> gpsObserver = CallbackObserver<MeshService, void *>(this, &MeshService::onGPSChanged);
+    CallbackObserver<MeshService, const meshtastic::GPSStatus *> gpsObserver =
+        CallbackObserver<MeshService, const meshtastic::GPSStatus *>(this, &MeshService::onGPSChanged);
     CallbackObserver<MeshService, const MeshPacket *> packetReceivedObserver =
         CallbackObserver<MeshService, const MeshPacket *>(this, &MeshService::handleFromRadio);
 
@@ -85,7 +87,7 @@ class MeshService
 
     /// Called when our gps position has changed - updates nodedb and sends Location message out into the mesh
     /// returns 0 to allow futher processing
-    int onGPSChanged(void *arg);
+    int onGPSChanged(const meshtastic::GPSStatus *arg);
 
     /// Handle a packet that just arrived from the radio.  This method does _not_ free the provided packet.  If it needs
     /// to keep the packet around it makes a copy