Iconfont icons are of no value to screenreader users; in our case,
they get alternative text. By adding 'aria-hidden="true"' to the
<span> holding the iconfont icon, we avoid the screenreader trying
to announce the iconfont icon.
- Only fire JS equal heights if flexbox is not supported
- Add flexbox styles for backend sections that used to use
JS based equal heights
- Use Modernizr's flexbox detection to use the old styles
as a fallback for non-flexbox browsers
- Generate new oldie stylesheet
- Do not use .clearfix with flexbox (Safari doesn't like it)
- Apply IE11 fix for flexbox, see goo.gl/pglrbm
References #333
Combine additional jquery/plugin files into one
Remove single file references
Moved dragdrop.js to serendipity_Editor.js.
Please test. Might make trouble in the installer/upgrader?
