Switch over to Hadoop CDH5.0.2

This is a forked pull-request to supersede #19 with updated documentation. I would have done a rebase but that would destroy @amiorin's author in his commit.

Ping @brndnmtthws for feedback.

Is this worthy of a version bump?
Heh, no problem. It took me a while to figure this one out – and I found almost nothing on the web about it... worth documenting.