Reworked lumping

So I took a stab at "cleaning up" our lumping code.  In the process, I fixed the warning issues Dan mentioned.  

Can someone tell me if this layout is cleaner than the previous one?  Some of the key changes are:

PCCA, PCCAPlus objects
Multiple files
Cleaned up the PCCA+ barrier penalty stuff
Raise an error if PCCA+ somehow settles for a non-feasible point