SSB-47: add entrypoint for docker image to source lofar code

CAL/Docker/HolographyBuild/Dockerfile

@@ -11,3 +11,4 @@ RUN mkdir -p /root/src/build/gnucxx11_debug
 WORKDIR /root/src/build/gnucxx11_debug
 RUN cmake ../../ -DUSE_LOG4CPLUS=OFF -DBUILD_PACKAGES=CAL -DCMAKE_INSTALL_PREFIX=/opt/lofar
 RUN make install
+COPY ./entrypoint.sh /root/entrypoint.sh

CAL/Docker/HolographyBuild/entrypoint.sh

+#!/usr/bin/env bash
+source /opt/lofar/lofarinit.sh
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