Proxy Objects revisited!

The first incarnation assumed that proxies were local objects per
definition. Unfortunately that makes it impossible to - for example -
reference-link an entire Scene with proxies, to be used as a special
character set.

This commit makes the proxy implementation also a bit more clear.

Related work: the scene-sets were not executed fully or correctly for
the dependency graph. That happens now (in 3d view) as well.

source/blender/src/poseobject.c

@@ -177,7 +177,7 @@ static int pose_has_protected_selected(Object *ob, int only_selected)
 {
 	
 	/* check protection */
-	if(OB_IS_PROXY(ob)) {
+	if(ob->proxy) {
 		bPoseChannel *pchan;
 		bArmature *arm= ob->data;