Add a percent identity filter to get_reciprocal_orthos.py so that sequences are
only stored as reciprocals if they had greater than a given hit percentage
(the number of identical bases divided by the hit length).

Add filtering option to mergeReciprocalOrthos.py so that it will only output
orthologs for which more than a given cutoff of species have representative

Coupling these two new filtering options lets you select only those orthologs that
seem to be nearly complete genes and found most or all of the species considered.