Relations were inserted by TYPO3's DataHandler after indexing and were
therefore not indexed.
We now use a later hook after DataHandler has finished everything, so we
know that we can index. As it's not relevant, we do not differentiate
between add and update anymore, as both trigger "indexDocument" internal.
Resolves: #112
* Add typoscript option which TYPO3 tables should be processed and which
should not be processed.
* Respect new optiion in hook.
* Also add necessary tests.
* Remove old no longer needed tests for hook.