[RTC] - Fix top pom to reference right plugin

[Jeff Genender]

The packaging plugin is at 1.2-SNAPSHOT, and the pom references it as
1.2.0. I wan tto update it to 1.2-SNAPSHOT:

Index: pom.xml
===================================================================
--- pom.xml     (revision 418149)
+++ pom.xml     (working copy)
@@ -136,7 +136,7 @@
          | Geronimo plugin versions
          |
          -->
-
<geronimoPackagingPluginVersion>1.2.0</geronimoPackagingPluginVersion>
+
<geronimoPackagingPluginVersion>1.2-SNAPSHOT</geronimoPackagingPluginVersion>

         <!--
          |