The Transitioner's role in life is to make the PolicyEngine's dreams a reality. That is, it takes a computed next state for the cluster (and a list of actions?) and attempts to reach it by instructing the LocalResourceManager on remote nodes to start and stop resources.
More information will appear here as work on the Transitioner and the NewHeartbeatDesign continues.
Also refered to as TransitionEngine or TE or TEngine depending on the phase of the moon.