Changes to N5s atomtype.  Decrement bond to N3s.  Form bond to N5s.
Changes to N5s atomtype.  Decrement bond to N3s.  Form bond to N5s.

We expect when N5s breaks a bond for resonance to appear, making
the atomtype N3s.

chatelak/RMG-Py,faribas/RMG-Py,nyee/RMG-Py,nyee/RMG-Py,comocheng/RMG-Py,nickvandewiele/RMG-Py,pierrelb/RMG-Py,comocheng/RMG-Py,KEHANG/RMG-Py,enochd/RMG-Py,nickvandewiele/RMG-Py,pierrelb/RMG-Py,chatelak/RMG-Py,enochd/RMG-Py,KEHANG/RMG-Py,faribas/RMG-Py