Depend on elasticsearch-parent

To simplify plugins maintenance and provide more value in the future, we are starting to build an `elasticsearch-parent` project.
This commit is the first step for this plugin to depend on this new `pom` maven project.

Remove a remaining sysout debug thing :(

Author: dadoonet

src/test/java/org/elasticsearch/memcached/test/AbstractMemcachedActionsTests.java

@@ -64,8 +64,6 @@ public void startMemcache() throws IOException {
     public void stopMemcache() {
         if (memcachedClient != null) {
             memcachedClient.shutdown();
-            boolean b = memcachedClient.waitForQueues(0, TimeUnit.MILLISECONDS);
-            System.out.println("b = " + b);
         }
     }