L2SS-497: Install stub tables, leaving the actual installation to the python code

docker-compose/lofar-device-base/Dockerfile

@@ -6,10 +6,13 @@ RUN sudo apt-get update && sudo apt-get install -y git && sudo apt-get clean
 COPY lofar-requirements.txt /lofar-requirements.txt
 RUN sudo pip3 install -r /lofar-requirements.txt
 
-# install and use ephimerides and geodetic ("measures") tables for casacore
+# install and use ephimerides and geodetic ("measures") tables for casacore.
+# we install a _stub_ since the tables need to be deployed explicitly from within the software.
 RUN sudo mkdir -p /opt/IERS && sudo chmod a+rwx /opt/IERS
-RUN IERS_DIRNAME=IERS-`date +%FT%T` && mkdir -p /opt/IERS/${IERS_DIRNAME} && ln -sfT /opt/IERS/${IERS_DIRNAME} /opt/IERS/current
-RUN cd /opt/IERS/current && curl ftp://ftp.astron.nl/outgoing/Measures/WSRT_Measures.ztar | tar xz
+ARG IERS_DIRNAME=IERS-1970-0101T00:00:00-stub
+COPY WSRT_Measures_stub /opt/IERS/${IERS_DIRNAME}
+RUN ln -sfT /opt/IERS/${IERS_DIRNAME} /opt/IERS/current
+
 COPY casarc /home/tango/.casarc
 
 ENV TANGO_LOG_PATH=/var/log/tango