Workflow:watch does not allow for watching in-progress workflows

[ian-rose]

Expected behavior

Running workflow:watch should have an option to watch a workflow already in process. Other workflow:* commands have an --id=xxx argument allowing specifying existing workflows, workflow:watch should support this argument as well.

Actual behavior

There is no (documented) ability to watch an in-process workflow that started before the terminus workflow:watch command was run.

Steps to reproduce the behavior

Start any workflow within Pantheon, attempt to use terminus to watch it.

[stovak]

Adding to feature requests.