Revert "Drop latex listing adapters in favour of good old basic classes."

This reverts commit abbf657af675194370d4e79caab6b02ec71670a2.

Conflicts:
	opengever/latex/listing.py
Merge pull request #553 from 4teamwork/pg_readd_latex_listing_adapters

Revert "Drop latex listing adapters in favour of good old basic classes....