Filter containers by status.

A continuation of #7616.
Closes #7616.
Adds `docker ps --filter=status=(restarting|running|paused|exited)` option.

Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jess@docker.com> (github: jfrazelle)
I'd rather have this as ID but no biggie if it LGT everybody else.
Because not sure about being consistent with faulting and erring side of things - unless of course there is an on-the-way PR to fix this en masse.