Wildcard tube matching (incl new tubes)

One drawback to our current docker setup is that services like mysql and beanstalk are not isolated between 99designs services (contests / swiftly etc).

This issue doesn't manifest for mysql, as (most) applications are isolated from each other at a database level. Unfortunately it does manifest for beanstalk, as `cmdstalk`, when run with `-all` will happily listen to queues from all applications.

While this problem is better addressed at a docker level, one feature that would alleviate this in the short term is wildcard tube matching.

Something like the following could listen to all present and future tubes starting with "contests_":
`cmdstalk -cmd="/path/to/your/worker --your=flags --here" -tubes="contests_*"`

Happy to pair with someone on it, for the go experience.