Vagrant and MPI_THREAD_MULTIPLE

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Currently we use the Ubuntu Boost packages when provisioning the Vagrant VM (https://github.com/xdata-skylark/libskylark/blob/development/vagrant/trusty64/bootstrap.sh#L68). As for Travis we should use mpich and compile Boost (see https://github.com/xdata-skylark/libskylark/blob/development/script/bootstrap-travis-deps#L6) in order to avoid the MPI_THREAD_MULTIPLE issue (MPI_THREAD_MULTIPLE: WARNING: Could not achieve THREAD_MULTIPLE support., see) or switch to OpenMPI >= 10.1.3.