Name change and bugfix
Renamed from parse_reaction.py to parse_KEGG.py in anticipation of adding abilities to parse other
KEGG files (compound and glycan).  Also fixed a bug where all reactions would be listed as not
being reversible.
metab_network.py to rxn centric
Changed to work with reactions and not KO's.  In future should either make separate script that
works with KO's from old version or merge new and old.
emergency commit, stuff works