actually return multipart!
downsampling of textures integrated
(Not tested, cause the §%$%& vagrant is in limbo again!)
parse layer, time interval & bbox from request
do not send cllada file and append time in .json geometry ids
database queries connected to request & general cleanup
create a temp directory for the gltf conversion
- Refactoring of the mesh_cache to follow 'MapCache' terminology (in future thie mesh_cache could be integrated as MapCache module, this python implementation can be seen as a proof-of-concept)
- The mesh_cache is storing the .json file in a sqlite db, additional glTF files (images, bin, shaders) are currently stored in an accessible apache directory
- Minor changes to the mesh_factory
Merge branch 'fha-mapcache-backend' into fha-mesh-cache
correct normalizing of U coordinate
Merge remote-tracking branch 'origin/vrvis-experimental' into fha-mesh-cache

Conflicts:
	vmanip_server/mesh_factory/ows/w3ds/v10/getscene.py
Fixed error in converstion from 'tiling schema to WGS84 coordinates' calculation
Minor changes