updated docker file and added stage for building docker image in ci pipeline

.gitlab-ci.yml

+stages:
+- docker
+- build
+
+buildDockerMXNetMaven:
+  stage: docker
+  tags:
+    - shell
+  script:
+    - cd docker
+    - docker login registry.git.rwth-aachen.de -u someUserName -p yEep-tAtl9HbsmNQJMNo
+    - docker build -t registry.git.rwth-aachen.de/monticore/embeddedmontiarc/applications/reinforcement_learning/forestrl/mxnetmvn:v0.0.1 .
+    - docker push registry.git.rwth-aachen.de/monticore/embeddedmontiarc/applications/reinforcement_learning/forestrl/mxnetmvn:v0.0.1
+  only:
+    changes:
+      - docker/*
+
 TestBuild:
-  image: registry.git.rwth-aachen.de/monticore/embeddedmontiarc/applications/reinforcement_learning/forestrl
+  image: registry.git.rwth-aachen.de/monticore/embeddedmontiarc/applications/reinforcement_learning/forestrl/mxnetmvn:v0.0.1
+  stage: build
   script:
     - maven clean install -s settings.xml

docker/Dockerfile

@@ -33,17 +33,9 @@ RUN apt-get install -y libopencv-dev
 RUN git clone --recursive https://github.com/apache/incubator-mxnet.git mxnet_source && \
     cd mxnet_source && git checkout tags/1.5.0 && cd .. && \
     cp -r mxnet_source/include/mxnet /usr/include/mxnet
-RUN pip install mxnet
+RUN pip install numpy==1.16.5 mxnet==1.5.0
 RUN cp -r "$(dirname $(python -c 'import mxnet; print(mxnet.__file__)'))/libmxnet.so" /usr/lib
 
-# OpenAI Gym
-RUN git clone https://github.com/openai/gym.git openai_gym && \
-    cd openai_gym && \
-    pip install -e . && \
-    pip install -e '.[box2d]' && \
-    pip install -e '.[atari]' && \
-    cd ..
-
 # Numpy Library
 RUN rm -rf /usr/include/numpy && \
     ln -s "$(python -c 'import numpy; print(numpy.get_include())')/numpy" /usr/include