Accept an Array of URL's, so both host AND port can be specified

If testing locally, or if nodes are running on different ports, there is no way to specify to connect to Host A, on Port B. Passing in an array of hosts is good - but it doesn't work if a cluster is running on a single computer (such as for testing, or when two brokers are running on the same computer).

To fix this, I changed what you should pass in as an Array. Rather than passing in the hosts as an Array, pass in the url: as an Array, and the host/port are parsed out of that.

This REMOVES the host Array functionality, I figured since this hadn't been released as 0.1.5 we could change it. But I can add backwards compatibility if necessary.