No more 'js_console' & styles

- the 'js_console' feature is removed as it is not relevant in that library
- the only styles left were the 'hidden' attribute so I removed the CSS stylesheet and
  added the 'hiden' snippet in the README (...)
new demo corrections following #6c57bfb
upgrading to 0.0.8@dev (after 0.0.7 release)