Closed requested to merge amezin/gtk:fix-postinstall-no-pkgconfig into master
PATH. If GLib is built as a subproject, this will allow running
gio-querymoduleswithout full path.
Don't fail when
pkg-configis not available. Just try to run everything without full paths (as if pkg-config variables were unavailable).
Also use argparse to parse command line arguments.
Fixes #3723 (closed)