remove nupic because python 2.7

src/Dockerfile.usefulpackages

@@ -31,7 +31,7 @@ RUN jupyter labextension install @ijmbarr/jupyterlab_spellchecker
 #RUN conda install -c anaconda caffe-gpu
 RUN conda install -c conda-forge theano
 RUN conda install -c conda-forge gym
-RUN pip install --no-cache-dir nupic
+#RUN pip install --no-cache-dir nupic
 RUN fix-permissions /home/$NB_USER
 
 # Switch back to jovyan to avoid accidental container runs as root