'juju run-action' should have a --wait option

[Tim Penhey]

The normal way to retrieve results from an action is to call:
    juju action do <unit> <action name>
and copy the uuid output and put it into
    juju action fetch <uuid>

I would like to be able to ask for an action to be executed, and say that I'm happy to wait for the results.

[Robie Basak (racb)]

This is especially painful because there is no output format that just gives me the id for easy shell capture.

[Robie Basak (racb)]

Attached is a quick, partially tested workaround shell function.

Call it like this:

juju_action_wait_do my-service/0 foo

[Anastasia (anastasia-macmood)]

PR against develop (2.2): https://github.com/juju/juju/pull/7060

Thank you, Stuart \o/