Port remaining bits to gdbus and remove stray dbus-glib references
Drop the dbus-glib version check from configure, since nothing depends
on new dbus-glib any more.
Move nm-dbus-glib-types.h and nm-gvaluearray-compat.h from include/ to
libnm-util/ since they are now only used by libnm-util and libnm-glib.
