Added test to show failure of matching topics starting with a slash
Made the resolver more permissive. Fixed issue where topics starting with a / would never resolve.
Merge pull request #33 from dcneiner/slash-in-topic

Slash in topic prevents the topic from resolving.
Fixed bug reported by @tsgautier in Issue #34. The publish call was incorrectly handling a mutating array of subscribers as it iterated over them. I also fixed the once() call to return the instance.