[NuSMV] NuSMVRunnerFactory currently not used
PROBLEM
NuSMVRunnerFactory is currently not necessary.
It should be determined whether it is to remove or not.
BACKGROUND
NuSMVRunnerFactory was used to choose one between NuSMVRunnner
and InteractiveNuSMVRunner. Since InteractiveNuSMVRunner was
removed, NuSMVRunnerFactory does not play any substantial role.
(from redmine: issue id 2308, created on 2015-03-10, closed on 2015-07-29)