Provide a way to remove one-off containers created by `docker-compose run`

[dnephin]

Related to: #2593 and #943
Copied from: #2568, #2184

One-off containers created by docker-compose run are not removed by default, and aren't removed by docker-compose rm.

We should do at least one of the following:

1. Make --rm flag default for fig run #943 - make --rm the default for run
2. add a flag to rm to include one-off containers
3. remove one-off containers as part of rm by default

[dnephin]

I don't have a strong preference for any of these, but I think we should do at least one of them for 1.7

[Visgean]

There are some other options:

• create another command with this behaviour - something like execute
• let users choose the behaviour in docker-compose config file

[mixja]

Another issue is even if you use docker-compose run --rm to remove the container, any volumes in the container are left behind as dangling volumes.

docker-compose rm -f -v does not deal with these dangling volumes, nor does docker-compose down

Note this does not reflect the behaviour of docker run --rm, which does remove volumes

[Kukunin]

I vote for 2nd option.

I use docker-compose in the CI environment (Jenkins), and I run tests with run off command, then use docker cp to get tests results from container and then clean after yourself with docker-compose stop and docker-compose rm. However, it doesn't remove run off container, so I need additional command.

Even I'd use volumes to get test results immediately on host machine, docker-compose run --rm doesn't clean volumes after itself (as far as I know)

[dnephin]

This was done in #3178