This insert files to the Xcode and Visual Studio projects, so you can add
sources to the build without having to find a Mac or Windows machine with
the appropriate tools installed, and manually update four different sets of
projects across them.
This doesn't touch CMake, but you can add files to that with a text editor
(hopefully) without drama.
This, like all Perl code, is fragile. Report bugs and don't push it too hard.
