Added categorizemismatch.py to categorize mismatches by type
(A to C, C to G, etc)
Added sortbarcodes-zd.py to do the same thing as sortbarcodes.py but
for data with 14-16mers instead of 12mers.
Added compare12merquality-zd.py to work with 14-16mer instead of
12mers. This and sortbarcodes-zd.py could be combined with their
non-zd counterparts to make a more generic script but it would
take some refactoring. This would require accounting for
ambiguous bases in the sticky end (W, R, etc.) in a generic
way rather than hardcoding for the specific W expected in the
ApeKI sticky end as I currently do.