Show number of messages waiting in queue

[rbuch]

Original issue: https://charm.cs.illinois.edu/redmine/issues/618

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Some indication of the number of available tasks on each PE (i.e. for each PE, a graph of message queue size vs. time) would be useful to identify situations where a PE is starved or overworked.

[PhilMiller]

Original date: 2015-02-11 06:20:22

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Passing open Projections Features with non-existent or departed assignees to Ronak for triage and re-assignment.