* clutter/clutter-actor.c (parse_units),
(clutter_actor_parse_custom_node),
(clutter_scriptable_iface_init): Override the parsing code
for the x, y, width and height properties of ClutterActor,
to allow strings with modifiers when defining the position
and/or the dimensions of an actor. Bare integers are assumed
as pixels; floating point values in the [0, 1] interval are
assumed as percentages; strings can have these modifiers:
- px - pixels
- mm - millimeters
- pt - points (at the current resolution)
- % - percentage of the stage
* clutter/clutter-units.h: Fix the conversion macros
* tests/test-script.json: Test the new values.