Method DownCast() is made template, to be available only when argument is actually a pointer or handle to a base class.
For compatibility with existing code, method DownCast() that can be used for the same type, derived, or unrelated class (i.e. where there is no actual down casting) is still available, its use shall cause "deprecated" compiler warning.
OCCT code is updated to remove meaningless DownCast()s; a few places where DownCast() was used with argument of unrelated type are corrected.
DRAW command QAHandleCast is removed (it was useful only during redesign of handles).
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.
