Renamed Layer to ServiceLayer for distinction from the Josm Layer class.
Improved download procedure and added option to download OSM data
for the same bounding box.
- Added TagBuilder classes
- Added functionality for downloading subset of osm data using overpass
- Fixed bug: error message when not downloading osm data
- Fixed bug: undesired downloading of osm data into openservices layer
- Fixed bug: can't reopen openservices layer after closing it
release 0.2.1
Fixed a small bug