message: updated generate_bottle.sh
diff: #! /bin/bash
  -VERS=`sw_vers -productVersion | awk '10\.13\..*/{print $0}'`
  -if [-z $VERS];
  +VERS=`sw_vers -productVersion | awk '/10\.13\..*/{print $0}'`
  +if [[ -z "$VERS" ]];
  then
  - VERS=`sw_vers -productVersion | awk '10\.14\..*/{print $0}'`
  - if [-z $VERS];
  + VERS=`sw_vers -productVersion | awk '/10\.14\..*/{print $0}'`
  + if [[ -z "$VERS" ]];
  then
  echo "Error, unsupported OS X version"
  exit -1
  