parameterIndex to order parameters

hrt/shgraph/ShaderParam.hx

@@ -46,6 +46,7 @@ class ShaderParam extends ShaderNode {
 
 	private var parameterDisplay : String;
 	private var displayDiv : hide.Element;
+	public var parameterIndex : Int;
 	public function setName(s : String) {
 		parameterName = s;
 		if (eltName != null)