[Hawkular-dev] agent auto-scan, inventory update

I think I finally got the agent working much better than before. In the past: 1) the agent would scan for inventory and once it got that inventory, that was it. It could never detect any new resources unless you restarted it 2) the agent would never detect changes to resource configuration properties even for resources it found on the original scan I think I fixed both now. The agent will scan periodically for new resources and add them to hawkular-inventory when it finds them. It will also detect if existing resources changed their resource configuration, if so, it will send those changed resources to hawkular-inventory. I also fixed it where it will no longer send the ENTIRE inventory EVERY scan. The agent will only send resources to inventory that are new or changed to the agent. All of this is in master. I wanted to release the agent with this new stuff, but I need h-inventory to do a release first (agent and command-gateway have srcdep dependencies on it).