Generate code for permission store proxy
Generate code for permission store proxy

This commit generates the code for the permission
store interface. Subsequent commits will use it.

Closes: #1837
Approved by: alexlarsson

flatpak/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,flatpak/flatpak