Use latest maven war plugin

git-svn-id: https://svn.apache.org/repos/asf/servicemix/smx4/kernel/trunk@757362 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/demos/smx4web/pom.xml b/demos/smx4web/pom.xml
index 5678395..ae8a45a 100644
--- a/demos/smx4web/pom.xml
+++ b/demos/smx4web/pom.xml
@@ -198,6 +198,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-war-plugin</artifactId>
+        <version>2.1-beta-1</version>
         <configuration>
           <warSourceDirectory>src/main/webapp/</warSourceDirectory>
           <webResources>