if bearing change then update the user location
fix scale gesture after last modifications to the mapController
double is better!
do NOT compute center based on boundingBox. The boundingBox (for now, should we change it?) is rounded in the sense that it uses scrollX and scrollY as int.
Instead use the computed mDScrollX and mDscrollY which are double
userAction optional parameter for most methods. Very important if you want to have custom "influence" on userlocation overlay "isFollowing"
More work done on concurrent animations. In this case we handle setZoom while scrolling animation