Merge branch Issue#171 with dev

Update to jflow.min.js and jflow.min.css

• The method to minify jflow's sources to jflow.min.js (https://github.com/mishoo/UglifyJS2) was to advanced, and generated errors in the code. We went back below the version 3, to avoid the script being broken when minified.

• The JQuery request 'get_user_files' was bugged because it was trying to reach ng6-test without the port '8080'. More information in this jflow commit: jflow@5c505644

issue #171 (closed)