Fix graphing when several cycles depend no an async task.
Added shutdown handling for deleted run dir.
Add timeout handler to test suite.
Environment filtering for #781
Added a test for environment filtering.
Merge pull request #806 from arjclark/fix-shutdown-on-del-dir

fix failure to shutdown if a suite's run dir is deleted
Added an environment exclusion filter.
Updated filter documentation.
Space after comma.
Removed "poor suite design" slur!
Fix get-config test for new environment filter section.
Merge pull request #807 from hjoliver/781.environment-filtering

Support environment filtering
Merge pull request #790 from hjoliver/fix-async-task-graphing

Fix graphing when several cycles depend on an async task.