Merge pull request #6587 from RosettaCommons/roccomoretti/tetrazole
[Foldit] Fix protonation state of tetrazoles.
Tetrazoles have a pKa of 4.9 and are a carboxylate mimic.
Right now we're not properly deprotonating them, change the charge state heuristics to better capture their physiologic state.
RELEASE NOTES: Better handling of tetrazole protonation states.