Issue #2526150 by catch, Wim Leers, Denchev, hussainweb, dawehner, mpdonadio, borisson_, fgm, olli, alexpott, vaplas, flocondetoile, Berdir, Fabianx, cilefen: Database cache bins allow unlimited growth: cache DB tables of gigabytes!

Revert "Issue #2526150 by catch, Wim Leers, Denchev, hussainweb, dawehner, mpdonadio, borisson_, fgm, olli, alexpott, flocondetoile, Berdir, Fabianx: Database cache bins allow unlimited growth: cache DB tables of gigabytes!"

This reverts commit 1a71b1a9.

Issue #2526150 by catch, Wim Leers, Denchev, hussainweb, dawehner, mpdonadio, borisson_, fgm, olli, alexpott, flocondetoile, Berdir, Fabianx: Database cache bins allow unlimited growth: cache DB tables of gigabytes!

Issue #2687897 by dawehner, jhedstrom, catch, jibran, Berdir, klausi: Convert system module's kernel tests to NG

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2386161 by Berdir, Wim Leers, beejeebus, olli: ChainedFastBackend doesn't set 'expires' and 'tags' when writing to fastBackend