Handle graphviz not being available during test_fsm
Handle graphviz not being available during test_fsm

isislovecruft/txtorcon,sammyshj/txtorcon,meejah/txtorcon,sammyshj/txtorcon,ghtdak/txtorcon,meejah/txtorcon,ghtdak/txtorcon,david415/txtorcon,isislovecruft/txtorcon,david415/txtorcon