Parallel module (NeuralEnsemble#307)

* ProcessPoolExecutor
* MPIPoolExecutor
* MPICommExecutor

.travis.yml

@@ -26,7 +26,7 @@ matrix:
       env: DISTRIB="pip"
       before_install: sudo apt install -y libopenmpi-dev openmpi-bin
       before_script: pip install -r requirements/requirements-extras.txt
-      script: mpiexec -n 1 nosetests --with-coverage --cover-package=elephant
+      script: mpiexec -n 1 python -m mpi4py.futures -m nose --with-coverage --cover-package=elephant
       after_success: coveralls || echo "coveralls failed"
 
     - name: "conda 3.7"
@@ -50,8 +50,10 @@ install:
       source "$HOME/miniconda/etc/profile.d/conda.sh";
       conda config --set always_yes yes;
       conda update conda;
+      sed -i "s/python>=[0-9]\.[0-9]/python=${TRAVIS_PYTHON_VERSION}/g" requirements/environment.yml;
       conda env create -f requirements/environment.yml;
       conda activate elephant;
+      conda uninstall -y mpi4py;
       pip list;
     else
       pip install -r requirements/requirements.txt;

doc/modules.rst

@@ -15,6 +15,7 @@ Function Reference by Module
    reference/kernels
    reference/neo_tools
    reference/pandas_bridge
+   reference/parallel
    reference/phase_analysis
    reference/signal_processing
    reference/spade

doc/reference/parallel.rst

@@ -0,0 +1,5 @@
+========
+Parallel
+========
+
+.. automodule:: elephant.parallel

doc/tutorials.rst

@@ -46,3 +46,17 @@ Advanced
 
   .. image:: https://mybinder.org/badge.svg
      :target: https://mybinder.org/v2/gh/NeuralEnsemble/elephant/master?filepath=doc/tutorials/gpfa.ipynb
+
+
+Additional
+----------
+
+* Parallel
+
+  ``elephant.parallel`` module provides a simple interface to parallelize
+  multiple calls to any user-specified function.
+
+  :doc:`View the notebook <../tutorials/parallel>` or run interactively:
+
+  .. image:: https://mybinder.org/badge.svg
+     :target: https://mybinder.org/v2/gh/NeuralEnsemble/elephant/master?filepath=doc/tutorials/parallel.ipynb