To many scrollbars in Chrome & Firefox

[peteruithoven]

Chrome:

This was cused by: #261
Which basicly created two overflow scroll rules:

• https://github.com/Doodle3D/doodle3d-client/blob/master/less/settingsPopup.less#L59 (original)
• https://github.com/Doodle3D/doodle3d-client/blob/master/www/css/settings.css#L20 (new)

We probbaly want to limit the newer one in settings.css to Y:

overflow-x: hidden;
overflow-y: scroll;

And remove the upper older one:

overflow: hidden;

This change would require some cross platform testing.