Add metrics-ganglia to core pom file

core/pom.xml

@@ -146,6 +146,10 @@
       <groupId>com.codahale.metrics</groupId>
       <artifactId>metrics-json</artifactId>
     </dependency>
+    <dependency>
+      <groupId>com.codahale.metrics</groupId>
+      <artifactId>metrics-ganglia</artifactId>
+    </dependency>
     <dependency>
       <groupId>org.apache.derby</groupId>
       <artifactId>derby</artifactId>