Update exists? to return true if group exists

[zachhale]

This seems like the best place to put this. There are many times when I want to check if a group exists and respond_to? :groupname doesn't work with simple config. Thoughts?

[weppos]

Hi @zachhale, thanks for the patch. Unfortunately, the patch causes a failure in the build and it's missing a spec associated with the changeset.

Moreover, I would kindly ask you to not commit changes to the .gitignore along with this patch, since they doesn't seem to match the scope of this pull-request.

As it is, I cannot merge this patch. Would you mind to update is according to the comments above? Can I also ask you to provide a practical example that would demonstrate what you are trying to accomplish?

[lukeredpath]

Closing in favour of #24 when I can get the build working.