CityGML 1.0 support, conversion of coordinates, support of polygons

• CityGML 1.0 is supported; legacy data sets should work now
• All thematic classes should now work (e.g. WaterBody)
• The finder of CityGML files now looks for the "xml" extension as well, no need to rename the file
• Option to convert (translate) the coordinates to a local system ("de-georeference"), useful for Blender
• Option to skip triangulation, and preserve polygons. Works only with polygons without interior.

Initial release (v0.1)

Initial release of the tool