This integrates the map widget from OpenPilot/GCS into a qt desinger plugin 

There are several limitation because of original code:
--> very bad performance
--> needs sqlite for caching 
--> scrolling error in opengl mode 
--> crashing if the zoom factor change is too big
--> caching is done into the current working directory 

Feel free to improve it. If someone wants to use it more regular 
it would be nice if we ask the people from OpenPilot to work together
so we do not have to wrap it 
