Stop and restart multiple processes by pid or name

Multi stop:
`bs stop 1111 2222 3333`
Multi restart:
`bs restart 1111 2222 3333`
Stop all:
`bs stop all`
Restart all:
`bs restart all`

fixes #18 
I was struggling on deciding what to do here. In hindsight what about throw the first (when all done) and log subsequent as they happen?