[!!!][TASK] Back to the future (6.2)

This is a task to upgrade to TYPO3 CMS 6.2 state of the art code, including:

* Migration from xml to xliff
* Replace t3lib_* calls by namespaced successors
* Remove XCLASS support
* Introduce namespaces for the extension classes

The extension works for me on 6.1, but there will be no support!

Resolves: #57399
Change-Id: I7f9c7b94c5daf9ecbeeb94fc65137fe7b00e031f
Reviewed-on: https://review.typo3.org/28921
Reviewed-by: Steffen Müller
Tested-by: Steffen Müller