Compare performance for phylo operations to castor

[jeromekelleher]

A tough competitor would probably be castor (source code here):

The author is here, so I could ask for assistance if we want. I'm not sure if it does the things we want to compare to, though? Some things it does in the overlap are: count_tips_per_node; find_farthest_tip_pair; get_all_distances_to_root; get_mrca_of_set; get_pairwise_mrcas; hsp_max_parsimony; asr_max_parsimony.

Originally posted by @petrelharp in #13 (comment)