TYPO3 Core

This is a refactor of BE module navigation. The menu is rendered with ExtJs producing the same markup as before (only removed an unnecessary div)
There is no inline javascript anymore with the module switcher, as all navigation info is loaded in an ExtJS Store.

On top of module menu is docheader first row which is result of ourt design team.

The frameset is removed completely, instead our navigation panel is used for navigation tree. Also navigation tree is only refreshed if the url changes.
I added loading masks to show loading, therefore i changed the loading mask background, as it was black before.

The javascript is backwards compatible, so all modules using old javascript still works.

Navigation panel is now collapsible and resizable, Menu panel is prepared to have the same, and there will be a solution in one of the next steps.
So i want to bring this in, as it looks the same as before, but speeds up the BE a lot.

(issue imported from #M15711)