Ability to cancel series run by other users

[smehta99]

I want to be able to cancel series run by other people in the same group using pav series cancel.

[Paul-Ferrell]

When a series gets it's cancel() method called, drop a 'CANCEL' file (or some other reasonable name) into the series directory. Then in the main series loop check for that file regularly. You'll probably have to pass the file path to any TestSet objects too, so they can test during builds and kickoff.

I usually like to wrap filesystem checks like that in some sort of timer based limiting.

[Paul-Ferrell]

Cancelling a series should trigger the cancellation of underlying tests by the '_series' process.

[Paul-Ferrell]

pav cancel <series_id> should cancel the series this way too.