This package is maintained in git, based on upstream's git repository at
https://github.com/openscad/MCAD. While no proper releases are done there, the
MCAD library is regularly included as a submodule in OpenSCAD releases; this is
where the Debian version numbers come from.

The submodules in SolidPython/ and ThingDoc/ were left out intentionally
because the openscad-mcad package only ships scad files. They don't need
special care for exclusion because they are maintained in submodules.
