prerequisites for html build during docs development (#349)

* updated the sphinx version using pip install in Dockerfile.ngraph_cpp

added a make target to build the docs to the contrib/docker/Makefile

* avoid upgrade pip message during build

contrib/docker/Dockerfile.ngraph_cpp

@@ -7,9 +7,17 @@ RUN apt-get update && apt-get install -y \
         clang-3.9 clang-format-3.9 \
         git \
         wget patch diffutils zlib1g-dev libtinfo-dev \
-        doxygen python-sphinx
+        doxygen python-pip
 
 RUN apt-get clean autoclean && \
     apt-get autoremove -y
+RUN pip install --upgrade pip
+
+# need to use sphinx version 1.6 to build docs
+# installing with apt-get install python-sphinx installs sphinx version 1.3.6 only
+# added install for python-pip above and
+# installed sphinx with pip to get the updated version 1.6.5
+# allows for make html build under the doc/source directory as an interim build process
+RUN pip install sphinx
 
 WORKDIR /home

contrib/docker/Makefile

@@ -75,6 +75,16 @@ build_docker: build_docker_image
 
 # Build
 
+doc:
+	# temporary html docs build until cmake docs commands are developed 
+	docker run --rm --tty \
+            ${VOLUME} \
+	    ${DOCKER_RUN_ENV} \
+            --env RUN_UID="$(shell id -u)" \
+            --env RUN_CMD="set -e ; set -o pipefail ; cd ${DOCKUSER_HOME}/ngraph-cpp-test/doc; env VERBOSE=1 make html 2>&1 | tee make_html.log" \
+            "build_ngraph_cpp:${DBUILD_VERSION}" \
+	    sh -c "${DOCKUSER_HOME}/ngraph-cpp-test/contrib/docker/run_as_user.sh"
+
 build_all: build_gcc build_clang
 
 build_gcc: build_docker_image