shared: remove unused libsystemd-dbus Polkit integration
shared: remove nearly unused spawn-polkit-agent helpers
fifo-control: make the unit file scope configurable through a file system flag by reading /run/systemd/arg-scope
util: indent in is_locale_utf8()
fifo-control: fix return type of get_arg_scope() to use UnitFileScope
fifo-control: add (hacky) function get_arg_root() to obtain unit file root path from file
tmpfiles.d: add entries for arg-scope and arg-root