Added GROUP_MEMBERS attribute to AbstractGroup
More helper methods to create ConfigKeys
Fix JAVA_OPTS replacement in environment for ActiveMQ and Jetty
Typo in messages for JMXRMI agent
Use JAVA_OPTS when launching ZooKeeper
Tidying up the ZooKeeper driver code

- Formatting and imports
- Use existing attributeSupplierWhenReady
Remove duplicate line when wrapping entity spec
Fix synchromization in CountdownTimerTest
Tidying up SSH driver new script with USE_PID_FILE constant
Tidying Cassandra driver script invocation command
Use supplier to resolve address of host
Short-circuit test for isJmxSslEnabled
Update CassandraNode driver with latest Brooklyn methods and revert change to scriptInvocationCommand
Add test assertions for GROUP_MEMBERS attribute
Add prepend StringFunction mirroring append
Further SSH driver tidying and canonicalisation across entities
Updating the Storm entity
Add classpath to java app launch
Updatiing Kafka SSH driver
Merge pull request #1299 from grkvlt/enhancement/group-members-environment-misc

Misc improvements and Tidyup