[Hawkular-dev] cmdgw and agent PR needs peer-review and merge

cmdgw PR: https://github.com/hawkular/hawkular-command-gateway/pull/51 agent PR: https://github.com/hawkular/hawkular-agent/pull/152 JIRA: https://issues.jboss.org/browse/HAWKULAR-790 I associated this with that JIRA because that JIRA is introducing a UI feature that requires it to know the current state of the statistics enabled flag on all the wildfly subsystems. These PRs provide the ability for the UI to ask the agent for that information. (NOTE: the agent PR can't be merged until the cmdgw PR is merged at which time I can take out the agent's cmdgw snapshot dependency)