[TASK] Fix TYPO3 6.1+ compat, remove dependencies to EXT:fed

I made all the fixes for TYPO3 6.1+ and completely removed the dependencies to EXT:fed
Where I could find a fitting ViewHelper in current EXT:vhs, I used that one, where I couldn't, I copied the ViewHelper to EXT:notify. Furthermore I copied needed services from EXT:fed to EXT:notify.
This, and the following parameter $sender, should have expected data types. And if I recall it correctly, the type should be "mixed" for this argument because Swift supports array $recipient, but I'm not sure about $sender...