cmtycmp: Fix NMI_LFK_python2.  Now complete and passes unit tests.
cmty: Add pajek (.clu) writing support
cmtycmp: Add nmiG (NMI with geometric mean denominator)

- I saw this used elsewhere, I am adding it for future inspection.
support/algorithms: call_process: Improve stdout descriptions
ioutil: add gexf and graphml to auto-detected formats.
cmtycmp: Add confusion matrix, frac_detected, vi_norm
support/algorithms: Add caching system
cache: Add cache module and caching decorator
tcmty: Add temporal community storage class and IO