Officially add the "cdn" folder to do cdn for some .js & .css files

1. Officially add the "cdn" folder to do cdn for some .js & .css files

2. Add sfo.min.js & sfo.min.css to do cdn for the project "sfo".
   The version of sfo is v0.0.8 .

3. Add sfo-lite.min.js & sfo-lite.min.css to do cdn for the project "sfo-lite".
   The version of sfo-lite is v0.0.5 .

4. Add highcharts3.js to let the style of highcharts 4 become highcharts 3.