use assertEquals (assertItemsEqual is not appropriate here)
status related handling now under supporting class StatusManager, which manages device_added/removed events, aggregate/rollup status updates and propagation of events, and also supports set_agent for the aggstatus of the platform itself.
merge upstream/master
Merge pull request #932 from carueda/platform_agent_R2C4

properly handle device_added/removed events and other additions and improvements