enables empty dummy nodes in DTD

An empty dummy node neither contains a regex nor a child node. Selecting
or deselecting it has no effect.

Author: memo

build.xml

@@ -2,7 +2,7 @@
 <project xmlns:ivy="antlib:org.apache.ivy.ant" name="NAMControllerCompiler" default="dist" basedir=".">
     <property name="targetversion" value="1.6" />
     <property name="sourceversion" value="1.6" />
-    <property name="project.version" value="0.3.10" />
+    <property name="project.version" value="0.3.11" />
     <property name="MyApp" value="${ant.project.name}" />
     <property name="MyApp-zipname" value="${ant.project.name}_${project.version}" />
     <property name="MyApp.jar" value="${MyApp}.jar" />

resources/xml/RUL2_IID_structure.dtd

@@ -1,5 +1,5 @@
 <!ELEMENT iid_tree (node+)>
-<!ELEMENT node (regex*,(regex|node),node*)>
+<!ELEMENT node (regex*,node*)>
 <!ELEMENT regex (requires*)>
 <!ELEMENT requires EMPTY>