[deform-texture] Add actor props, remove test code
[deform-texture] Add actor props, remove test code

Add properties for the actors that will be deformed when using
mx_deform_texture_set_actors and remove test code. Deforming actors now
works.

Also allow setting of one face as an actor and one face as a material.
When passing NULL as one of the parameters in
set_from_files/set_materials/set_actors, it will not remove the
corresponding actor/material.

e.g., you can do:
mx_deform_texture_set_materials ("image.png", NULL);
mx_deform_texture_set_actors (NULL, mx_button_new ());

and you will have the front face as an image and the back face as a
button.

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