This is to help ensure buildbot builds are correct, while still gracefully
disabling features in user/developer builds.
* Add WITH_STRICT_BUILD_OPTIONS to give an error when features can't be
enabled due to missing libraries or other reasons. Add new macro
set_and_warn_library_found used everywhere features were being
automatically disabled.
* Remove code from Windows and macOS for various libraries that would
automatically disable features. set_and_warn_library_found could be
used here also, but we are generally assuming the precompiled libraries
are complete and only test for availability when libraries are just
added.
Differential Revision: https://developer.blender.org/D16104
e7a6917617