message: build: make umd.min.js source map paths relative
  I'm not quite sure how to test this since we don't have any infrastructure for these kinds of tests.
  I did verify the fix manually though.
  Fixes
  PR Close
diff: @@ -206,7 +206,7 @@ minify() {
  base_file=$( basename "${file}" )
  if [[ "${base_file}" =~ $regex && "${base_file##*.}" != "map" ]]; then
  local out_file=$(dirname "${file}")/${BASH_REMATCH[1]}.min.js
  - $UGLIFYJS -c --screw-ie8 --comments -o ${out_file} --source-map ${out_file}.map --source-map-include-sources ${file}
  + $UGLIFYJS -c --screw-ie8 --comments -o ${out_file} --source-map ${out_file}.map --prefix relative --source-map-include-sources ${file}
  fi
  done
  }
  