action: prevent warnings when using MxAction with glib 2.28
action: prevent warnings when using MxAction with glib 2.28

The "name", "parameter-type", "enabled" and "state" properties were
construct writable in glib 2.28, but not in glib 2.30. Adding them to
set_property if compiled with a glib version less than 2.30.0 prevents
warnings when the constructor attempts to set the properties.

pwithnall/mx,pwithnall/mx,clutter-project/mx,clutter-project/mx,pwithnall/mx,jonnylamb/mx,jonnylamb/mx,clutter-project/mx,jonnylamb/mx,clutter-project/mx,jonnylamb/mx,pwithnall/mx