Feature/kasm 1838 libjpeg turbo from source (#49)

New build option with latest stable libjpeg-turbo library

builder/os_ver_cli.sh

@@ -3,6 +3,11 @@ default_os_codename=bionic
 
 os=${1:-$default_os}
 os_codename=${2:-$default_os_codename}
+build_tag="${3:-}"
+if [[ -n "$build_tag" ]]; then
+   build_tag_for_images="_${build_tag#+}"
+   build_debian_revision="$(echo $build_tag | tr _ -)"
+fi
 os_image="$os:$os_codename"
 
 echo "Building for $os_image"