Unable to down non project containers

[svrana]

When dev {project} down is run only the project container is shut down. Any other containers listed in the docker-compose files for the project are not brought down. This was intentional b/c dev doesn't really know the relationship between all the projects. Once issue #4 is resolved, flags can be added to the 'down' command to shut down all shared dependencies (probably should result in a warning that other dependent projects will also be shu down).

[jerryzxliu]

want to point out that, if there's another running container B that depends on the dependencies of container A, dev down on A should not bring down the dependencies of A that are also dependencies of B