L2SS-225: Remove calling a script to remove the images

Instead do it in the function itself in order to make it more
visible what is actually done.

bootstrap/sbin/rebuild_system_from_scratch.sh

@@ -32,7 +32,16 @@ function move_tango_dir_out_of_the_way()
 
 function remove_images()
 {
-    ${HOME_DIR}/bootstrap/sbin/delete_all_docker_images.sh YES_DELETE_ALL
+    images="$(for i in $(docker images | egrep -v "REPOSITORY" | awk '{printf "%s:%s\n", $1, $2}'); do printf "%s " ${i}; done)"
+    if [ ${#images} -eq 0 ]; then
+        echo -e "\tThere are no images to delete."
+    else
+        echo -e "\tWill now delete the following Docker images:"
+        for image in ${images}; do
+            printf "\t\t%s\n" ${image}
+        done
+        docker rmi "${images}"
+    fi
 }
 
 function pull_tango()