[TYPO3-core] Copyright-year in headers

[Benjamin Mack]

Hey Michael,

thanks again!

- I suggest to go with #9 (still) as this was also discussed and
approved with the association
- name it "TYPO3 CMS project" not "TYPO3 project"
- also, move GPL.txt to LICENSE.txt and that's it.

This is the state that was discussed and still way better than the
current situation.

Although this is not 100% like the FLOW project, I think that once we
have it this way (= safe) we can again check if we need the LICENSE.txt
file and adopt the headers again.

Sounds fair enough for everybody? If so, I'm fine with checking the
patch and merging it into the core, once you put it on Gerrit. K?

All the best,
Benni.