The collection of Python scripts here have gotten to the point where
we need to share code. Start refactoring things so that we have one
main command which imports subcommands as libraries.
Add a simple KEY=VALUE metadata file format, and rather than
assuming 'basename' at a low level, allow passing e.g. NAME=gtk3
to override "gtk+".
The wrapper scripts are annoying...for now let's just remove them.
One thing that made this take significantly longer than it might
have otherwise is that we have to keep PWD "up to date" - otherwise
we hit bugs in glibc's getcwd() implementation.
Colin Walters