Switch for only using active tasks

[Whitney Sorenson]

Seems like the default behavior is to run commands against completed as well as currently active tasks.

Most of the time (the default) should probably be active tasks only.

I imagine it is only rarely important to inspect the file sandbox for a completed task.

[Dr. Stefan Schimanski]

+1

[Joachim de Groot]

+1

[Tobi Knaup]

+1 for making active the default