Update runalltests.bash to include GenericSystemTest.  Also, the mpi run command can be set on the command line with --mpirun=<command>.  On Macs the default is mpiexec-openmpi-mp (following MacPorts)
Update runalltests.bash to include GenericSystemTest.  Also, the mpi run command can be set on the command line with --mpirun=<command>.  On Macs the default is mpiexec-openmpi-mp (following MacPorts)

git-svn-id: 602a26e73ae9f2a14e2bb95676f2e137fcc39919@8432 7c0444ca-5550-0410-9008-faecdbe78eb5

PetaVision/OpenPV,PetaVision/OpenPV,PetaVision/OpenPV,PetaVision/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,PetaVision/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV