Benp/paver tests

@clytwynec @muhammad-ammar 

Could you take a look?

I'm leaving out the subdir problem as that's something we're still vetting out. Note as well that we are not looking at coverage of paver right now; that's still going to be ignored at this point.

Ben

My main goal was to make sure it is run as part of `paver test`. I thought lib_test was intuitive (plus, admittedly, of the various unit testing commands, it had the least plumbinng IIRC). 

I'm glad to put it elsewhere if you think there's a better place...