Support list of regexes similar to list of names

Hi,

Thanks for the awesome work so far. Pumba lib has been very helpful for injecting container faults. 

We ran into a situation where we needed pumba to support list of regexes for selecting containers. Are there any limitations around why we are not supporting it yet? Insights would be helpful.

If there are no constraints around the requirement, I would be happy to pick it up.