change Docker context - installation of GNU parallel

docker/Dockerfile

@@ -15,7 +15,13 @@ RUN locale-gen en_US.UTF-8 && dpkg-reconfigure locales
 # some necessary dependencies, developer tools
 # set up the latest GNU parallel
 RUN apt-get install -y -q build-essential git wget curl python python-dev python-pip && \
-(wget -O - pi.dk/3 || curl pi.dk/3/ || fetch -o - http://pi.dk/3) | bash
+wget https://ftpmirror.gnu.org/parallel/parallel-20180822.tar.bz2 && \
+bzip2 -dc parallel-20180822.tar.bz2 | tar xvf - && \
+cd parallel-20180822 && \
+./configure && make && make install && cd .. && rm -rf parallel-20180822
+
+#&& \
+#(wget -O - pi.dk/3 || curl pi.dk/3/ || fetch -o - http://pi.dk/3) | bash
 
 # add scripts, executables, testdata (the target directories will be made automatically if they don't exist)
 ADD external_software /home/src/