use getDB instead of importing database to get forbidden structs
use getDB instead of importing database to get forbidden structs

in isMoleculeForbidden

database can now be either globally stored, or reside as a broadcasted
variable

pierrelb/RMG-Py,pierrelb/RMG-Py,nickvandewiele/RMG-Py,nyee/RMG-Py,nickvandewiele/RMG-Py,nyee/RMG-Py