Create BAS: check if study exists

Added check in the "create BAS" dialog to ensure that names of studies
don't get repeated
Google Maps and drawing canvas

Added map to the display (issues checking API v2 with only the
emulator); alternative to Google Maps that draws points on a canvas
(initial draft implementation; need to revise point transform)
Update drawing

Cleaned up the drawing and update connections. The device must have a
shapefile (polygon.shp) in the application's data folder.
Added package structure