BZ1099220 - Fix classloading issues with WildFly

The original problem was that some classes were being inadvertently picked up
from the parent classloader, and these classes could not see the client library
in turn.

This fix requires a version of EMS that allows ClassLoaders to be passed into
EMS advanced properties. See: https://github.com/genman/ems/tree/P136

One possibly controverisial change is having the JBossAS plugin depend on the
JMX plugin. This avoids having to add the JMX dependency as well.