Delete all the various forms of NPM cache

They clutter up the image and cause Twistlock to false positive

Dockerfile

@@ -120,9 +120,6 @@ RUN optipng -clobber -quiet static/img/**/*.png
 RUN apt-get remove -y --auto-remove python-dev g++ libjpeg62-dev libevent-dev libldap2-dev  libsasl2-dev libpq-dev libffi-dev libgpgme11-dev nodejs npm jpegoptim optipng
 RUN apt-get autoremove -y
 RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
-RUN rm -rf .npm
-RUN rm -rf grunt
-RUN rm -rf node_modules
 
 # Set up the init system
 ADD conf/init/copy_config_files.sh /etc/my_init.d/
@@ -157,6 +154,14 @@ ADD .git/HEAD GIT_HEAD
 ADD . .
 RUN pyclean .
 
+# Cleanup any NPM-related stuff.
+RUN rm -rf /root/.npm
+RUN rm -rf /.npm
+RUN rm -rf /usr/local/lib/node_modules
+RUN rm -rf /root/node_modules
+RUN rm -rf /node_modules
+RUN rm -rf /grunt
+
 # Run the tests
 ENV RUN_ACI_TESTS False
 ADD requirements-tests.txt requirements-tests.txt