[!!!][FEATURE] Introduce namespaces

this is the first commit that is breaking compatibility with
TYPO3 below 6.x. If you still want to continue with TYPO3
below 6.x please use the branch 1.9.x

Releases: master
Resolves: #51461
Change-Id: If1dbca2fa4fd16a00734f78201e7129cfcc6766e
Reviewed-on: http://review.typo3.org/34232
Reviewed-by: Simon Schaufelberger <simonschaufi@googlemail.com>
Tested-by: Simon Schaufelberger <simonschaufi@googlemail.com>