Update the location bubble on drag end.
Merge pull request #11 from b0ri5/update-bubble-location-on-dragdrop

Update the location bubble on drag end.
Intermediate, need to reboot or something. Everything's slow.
Center the map on the whole world if there are no markers. Center on all markers if there are any.
Merge pull request #12 from b0ri5/initial-viewport-all-pins

Center the viewport around all previously added markers.