1) Remove unnecessary includes of "Standard_OStream.hxx" file and add it only into files where it is really used.
2) Create the base interface for a file stream provider OSD_FileSystem and its inheritor OSD_CachedFileSystem that keeping last stream to be reused for opening a stream with the same URL.
3) Use OSD_CachedFileSystem object instead of RWGltf_GltfSharedIStream during Gltf reading.
Implementation of global functions STANDARD_TYPE() for types not inheriting Standard_Transient or Standard_Persistent are eliminated.
Global functions and class methods ShallowCopy() are removed; also removed unused classes Visual3d_PickPath and Visual3d_PickDescriptor.
Global functions and class methods ShallowDump() are removed, except for classes Standard_GUID, TopLoc_Datum, and TopLoc_Location as the latter are still used in some Debug printouts.
License statement text corrected; compiler warnings caused by Bison 2.41 disabled for MSVC; a few other compiler warnings on 54-bit Windows eliminated by appropriate type cast
Wrong license statements corrected in several files.
Copyright and license statements added in XSD and GLSL files.
Copyright year updated in some files.
Obsolete documentation files removed from DrawResources.
