Now using jmxtrans instead of built in ganglia support for Hadoop

The built in Hadoop Ganglia support does not work with multi-hop
multicast Ganglia setups.  jmxtrans is more tedious (each
JMX bean must be manually configured), but works.

Updating modules/cdh4 and modules/jmxtrans to get this to work as well.

Change-Id: Idde4a1be6b57602b90e3114309a86853f3c0a5ca