first try to support center geometries for osm-xml
fix parsing of ordinary ("skeleton") geometry
test all branches
add tests for "center" geometry
Merge branch 'gh-pages' into neogeometries

Conflicts:
	osmtogeojson.js
implement center geometry mode for the json data format
implement center geometry output mode in CLI tool
add object types consistently to verbose debug output

although most of the time quite ambiguous, this is necessary in
some cases of the new overpass output modes where a node can
actually be a pseudo-object resulting from a way's "center"
geometry, for example.
add output info for special geometry features

features.properties.geometry=="center" for features resulting from
object with an overpass api center geometry
implement bounds geometry mode

constructed features are Polygons spanning over the object's
bounding box.

They are identifiable via: properties.geometry == "bounds"
fix a bug where objects with "bound" geometry where overwritten by following objects

also, check in a build
Merge branch 'neogeometries' into gh-pages
2.1.0 release