Added Dockerfile

This repository is to run the Clickpleteness (or any other for that matter) web application.

Added licence and Dockerfile.

\approve @fd \fyi @ds @marius @nicgar

Dockerfile

+# Copyright (C) 2021:
+#   Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum GFZ
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or (at
+# your option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero
+# General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see http://www.gnu.org/licenses/.
+
+FROM node:latest
+
+RUN git clone https://git.gfz-potsdam.de/dynamicexposure/completeness/clickpleteness.git /app 
+
+WORKDIR /app
+
+RUN npm install -g npm@latest && npm install && npm run build
+
+EXPOSE 8080
+
+CMD ["node", "./srv/server.js"]