JM-175 -- don't keep the exploded plugin build in target/plugins.

git-svn-id: http://svn.igniterealtime.org/svn/repos/messenger/trunk@996 b35dd754-fafc-0310-a699-88a17e54d16e

build/build.xml

@@ -889,6 +889,9 @@
                 <fileset dir="${plugin.dest.dir}/@{plugin}" />
             </jar>
 
+            <!-- Delete the exploded plugin -->
+            <delete dir="${plugin.dest.dir}/@{plugin}" />
+
         </sequential>
     </macrodef>