Add --rm to docker run in Makefile
Add --rm to docker run in Makefile

So tests don't leave containers all over the place. The downside
is this makes it a bit harder to debug a test's filesystem -
you'll have to remove the "--rm" and run the test again.

Signed-off-by: Ben Firshman <73675debcd8a436be48ec22211dcf44fe0df0a64@firshman.co.uk>

vpetersson/docker-py,youhong316/docker-py,auready/docker-py,auready/docker-py,dimaspivak/docker-py,vdemeester/docker-py,dimaspivak/docker-py,bfirsh/docker-py,docker/docker-py,youhong316/docker-py,funkyfuture/docker-py,kaiyou/docker-py,kaiyou/docker-py,funkyfuture/docker-py,vdemeester/docker-py,vpetersson/docker-py,docker/docker-py,bfirsh/docker-py