Rework how system properties are passed into an mda invocation.

This allows new properties to be injected more easily, and allows Ant's property
hierarchy (including external property files) to be used to create new ones or
override old ones.

build.xml

@@ -442,6 +442,30 @@
 	    ***************************
 	-->
 
+	<!--
+	    Property definitions for the mda tool.
+	    
+	    Any Ant property with a name of the form "mda.*" is passed through
+	    as a system property to the mda invocation with the "mda." stripped
+	    off. Thus, a property "mda.foo" will be passed through as a system
+	    property called "foo".
+	    
+	    The individual properties listed here can be augmented or overridden
+	    by properties defined in the external properties files, e.g., build.properties.
+	-->
+    <property name="mda.java.endorsed.dirs" value="${tools.mda}/lib/endorsed"/>
+    <property name="mda.basedir" value="${basedir}"/>
+    <property name="mda.rulesdir" value="${rules.dir}"/>
+
+	<!--
+	    Build a property set of all the properties to be passed through, with
+	    the "mda." prefix stripped off.
+	-->
+	<propertyset id="mda.properties">
+        <propertyref prefix="mda."/>
+	    <mapper type="glob" from="mda.*" to="*"/>
+	</propertyset>
+
 	<!--
 	    Macro to run the mda (metadata aggregator CLI) tool.
 	-->
@@ -471,9 +495,9 @@
                         <include name="ukf-members-*.jar"/>
                     </fileset>
                 </classpath>
-                <jvmarg value="-Djava.endorsed.dirs=${tools.mda}/lib/endorsed"/>
-            	<jvmarg value="-Dbasedir=${basedir}"/>
-            	<jvmarg value="-Drulesdir=${rules.dir}"/>
+                <syspropertyset>
+                    <propertyset refid="mda.properties"/>
+                </syspropertyset>
             	<jvmarg value="-enableassertions"/>
             	<arg value="--quiet"/>
             	<arg value="@{config}"/>
@@ -1383,7 +1407,14 @@
         List all the properties ant is using.
     -->
     <target name="echoproperties">
+    	<echo>All properties:</echo>
         <echoproperties/>
+    	<echo>MDA properties:</echo>
+    	<echoproperties>
+    		<propertyset>
+    			<propertyset refid="mda.properties"/>
+    		</propertyset>
+    	</echoproperties>
     </target>
 
 </project>