change bulk_create call (unexpected speedup)
change bulk_create call (unexpected speedup)

for some reason this commit lead to a speedup, probably worth looking
into what Django internals are doing here

ne --import 77s -> 51s
nh --import 81s -> 59s

opencivicdata/pupa,datamade/pupa,datamade/pupa,rshorey/pupa,opencivicdata/pupa,influence-usa/pupa,influence-usa/pupa,mileswwatkins/pupa,rshorey/pupa,mileswwatkins/pupa