Added perturbation variances file
Merge branch 'master' of https://github.com/acliu/gs_mpi
Merge branch 'master' of https://github.com/acliu/gs_mpi
Merge branch 'master' of https://github.com/acliu/gs_mpi
Merge branch 'master' of https://github.com/acliu/gs_mpi
Carver script modifications