Modifying to allow more than 2 usernames for weare

Sometimes groups work together in the same branch.  This most often happens in phase one.  

I modified the weare portion that takes 2 usernames to allow more than 2 usernames.  In this form it currently allows any number.  

Doing this to facilitate better tracking to see who is really working together when scanning challenge branches in the student github orgs.

@quackingduck - Can you take a look?  This is my first attempt at Bashy goodness.