TYPO3 Core

With TYPO3 4.4, we introduced the option of allowing HTML 5 modules in the backend. I'd like to go one step further and switch to HTML5 as default. This is a prerequisite for a lot of good future developments like a multiple uploader in the BE with having Flash as fallback for all old browsers. Also, it also signals that we're not using just old technologies but are willing to push latest technologies as well (of course with fallbacks, we all know :)).

I tested this patch on Firefox; and IE6 and couldn't find any sideeffects after some testing. However, IE6 with trunk looks crappy because of PNGfix, which doesn't work.

(issue imported from #M15844)