2.5 - Demo of how to get node attributes animateable

* Made sure that nodes have a working 'path' function (needed for any tools that will resolve paths needed for animating properties)

* Replaced all the UI button controls for a single node (Vector Blur) with relevant RNA buttons which can be animated. There are probably some even nicer ways to do this (i.e. using layout engine for drawing all sets of buttons), though this is the easiest way forward in the immediate future. 
Anyways, if people are interested in getting this working, they will need to spend time to replace all the necessary button calls :)

source/blender/makesrna/intern/rna_nodetree.c

@@ -57,6 +57,15 @@ StructRNA *rna_Node_refine(struct PointerRNA *ptr)
 	}
 }
 
+static char *rna_Node_path(PointerRNA *ptr)
+{
+	bNodeTree *ntree= (bNodeTree*)ptr->id.data;
+	bNode *node= (bNode*)ptr->data;
+	int index = BLI_findindex(&ntree->nodes, node);
+	
+	return BLI_sprintfN("nodes[%d]", index);
+}
+
 #else
 
 #define MaxNodes 1000
@@ -1353,6 +1362,7 @@ static void rna_def_node(BlenderRNA *brna)
 	RNA_def_struct_ui_text(srna, "Node", "Node in a node tree.");
 	RNA_def_struct_sdna(srna, "bNode");
 	RNA_def_struct_refine_func(srna, "rna_Node_refine");
+	RNA_def_struct_path_func(srna, "rna_Node_path");
 	
 	prop = RNA_def_property(srna, "location", PROP_FLOAT, PROP_XYZ);
 	RNA_def_property_float_sdna(prop, NULL, "locx");