TYPO3 Core

Since r9160 (#23744) it's possible to use the FLUIDTEMPLATE TypoScript cObject.
The current implementation calls some non-API functions of Fluid and Extbase. This patch removes this strong dependency by using the new Fluid standalone view which encapsulates most of the complexity.
Note: After applying the patch FLUIDTEMPLATE still depends on Extbase. But all the Extbase logic is moved to Fluid, so it will be possible to unwire this without having to touch tslib_content again.

The changes this patch incorporates are mostly backwards compatible but there are some minor side-effects:
- The initialization of the Extbase autoloader did not work as expected. This is fixed in Tx_Fluid_View_StandaloneView
- After discussion with Sebastian and Benni, we decided that it does not make sense to set requestPluginName, requestControllerExtensionName, requestControllerName and requestControllerActionName to some (non-exisiting) default values
- There's a new setting "format" which defaults to "html" and allows you to easily create standalone views for other formats like xml
(issue imported from #M16173)