Stalling MPI tests

Created originally on Bitbucket by avmo (Ashwin Vishnu)

Both on Travis as well as on my laptop with a fresh virtualenv (see the present fluidinfo output).

<sys_info>
  <software CC="gcc (GCC) 8.1.1 20180531" MPI="mpirun (Open MPI) 3.1.0"
            distro="arch Arch Linux" hostname="kthxps" kernel="4.17.2-1-zen"
            system="Linux"/>  

  <hardware address_sizes="39 bits physical, 48 bits virtual" arch="x86_64"
            bogomips="4790.17" cache_size="4096 KB" cpu_MHz_actual="[1949.199,
            1803.38, 1800.223, 1779.628]" cpu_MHz_current="1833.107"
            cpu_MHz_max="3000.000" cpu_MHz_min="500.000" cpu_name="Intel(R)
            Core(TM) i7-5500U CPU @ 2.40GHz" nb_cores="2" nb_procs="4"
            nb_siblings="4"/>  

  <python compiler="GCC 8.1.0" implementation="CPython" version="3.6.5">
    <fluiddyn installed="True" local_path="/home/avmo/src/gfdyn/fluiddyn"
              remote_path="ssh://hg@bitbucket.org/gfdyn/fluiddyn"
              version="0.2.3"/>  

    <fluidsim installed="True" local_path="/home/avmo/src/gfdyn/fluidsim"
              remote_path="ssh://hg@bitbucket.org/gfdyn/fluidsim"
              version="0.2.1"/>  

    <fluidlab installed="False" local_path="" remote_path="" version=""/>  

    <fluidimage installed="False" local_path="" remote_path="" version=""/>  

    <fluidfft installed="True" local_path="/home/avmo/src/gfdyn/fluidfft"
              remote_path="https://bitbucket.org/fluiddyn/fluidfft"
              version="0.2.3"/>  

    <fluidcoriolis installed="False" local_path="" remote_path="" version=""/>  

    <fluiddevops installed="True"
                 local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/fluiddevops"
                 remote_path="" version="0.0.2b1"/>  

    <numpy installed="True"
           local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/numpy"
           remote_path="" version="1.14.5">
      <system>
        <lapack_opt define_macros="[('NO_ATLAS_INFO', 1), ('HAVE_CBLAS', None)]"
                    include_dirs="['/usr/local/include', '/usr/include',
                    '/scratch/avmo/opt/gfdyn/include']" language="c"
                    libraries="['lapack', 'lapack', 'cblas', 'blas']"
                    library_dirs="['/usr/lib64']"/>  

        <blas_opt define_macros="[('NO_ATLAS_INFO', 1), ('HAVE_CBLAS', None)]"
                  include_dirs="['/usr/local/include', '/usr/include',
                  '/scratch/avmo/opt/gfdyn/include']" language="c"
                  libraries="['cblas', 'blas']" library_dirs="['/usr/lib64']"/>  

        <fftw define_macros="[('SCIPY_FFTW3_H', None)]"
              include_dirs="['/usr/include']" libraries="['fftw3']"
              library_dirs="['/usr/lib64']"/>  

      </system>

      <build>
        <lapack_opt define_macros="[('HAVE_CBLAS', None)]" language="c"
                    libraries="['openblas', 'openblas']"
                    library_dirs="['/usr/local/lib']"/>  

        <blas_opt define_macros="[('HAVE_CBLAS', None)]" language="c"
                  libraries="['openblas', 'openblas']"
                  library_dirs="['/usr/local/lib']"/>  

      </build>

    </numpy>

    <cython installed="True"
            local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages"
            remote_path="" version="0.28.3"/>  

    <mpi4py installed="True"
            local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/mpi4py"
            remote_path="" version="3.0.0"/>  

    <pythran installed="True"
             local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/pythran"
             remote_path="" version="0.8.6"/>  

    <pyfftw installed="True"
            local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/pyfftw"
            remote_path="" version="0.10.3.dev0+e827cb5"/>  

    <matplotlib installed="True"
                local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/matplotlib"
                remote_path="" version="2.2.2"/>  

    <scipy installed="False" local_path="" remote_path="" version=""/>  

    <skimage installed="False" local_path="" remote_path="" version=""/>  

    <h5py installed="True"
          local_path="/scratch/avmo/opt/gfdyn/lib/python3.6/site-packages/h5py"
          remote_path="" version="2.8.0">
      <config HDF5_version="1.10.2" MPI_enabled="False"
              single_writer_multiple_reader_available="True"
              virtual_dataset_available="True"/>  

    </h5py>

  </python>

</sys_info>