mpi-less baselines (#689)

* make baselines run without mpi wip

* squash-merged latest master

* further removing MPI references where unnecessary

* more MPI removal

* syntax and flake8

* MpiAdam becomes regular Adam if Mpi not present

* autopep8

* add assertion to test in mpi_adam; fix trpo_mpi failure without MPI on cartpole

* mpiless ddpg

Dockerfile

@@ -1,16 +1,7 @@
-FROM ubuntu:16.04
+FROM python:3.6
 
-RUN apt-get -y update && apt-get -y install git wget python-dev python3-dev libopenmpi-dev python-pip zlib1g-dev cmake python-opencv
+# RUN apt-get -y update && apt-get -y install git wget python-dev python3-dev libopenmpi-dev python-pip zlib1g-dev cmake python-opencv
 ENV CODE_DIR /root/code
-ENV VENV /root/venv
-
-RUN \
-    pip install virtualenv && \
-    virtualenv $VENV --python=python3 && \
-    . $VENV/bin/activate && \
-    pip install --upgrade pip
-
-ENV PATH=$VENV/bin:$PATH
 
 COPY . $CODE_DIR/baselines
 WORKDIR $CODE_DIR/baselines