Fixed imagery rendering issues. Robot position in Pixhawk3DWidget is now derived from the global pose (lat/lon/alt) instead of the local pose.

I added the ability for the parser to pack an array of any mavlink standard type.  This will allow array types to be specified for mavlink messages without using the type="array" syntax.

I also changed how a bunch of the strings were constructed to more closely conform to the coding style guidelines by reducing the number of implicit copy constructor calls