Issue #2057401 by plach, socketwench, kfritsche, Damien Tournoud: Fixed Make the node entity database schema sensible.

Revert "Issue #2057401 by plach, socketwench, kfritsche: Fixed Make the node entity database schema sensible."

HEAD broken; rolling back temporarily.

This reverts commit c72f39ad.

Issue #2057401 by plach, socketwench, kfritsche: Fixed Make the node entity database schema sensible.

Issue #2079011 by Berdir, alexpott: Move field.module constants related to storage to EntityStorageControllerInterface.

Issue #1497374 by yched, chx, amateescu, plach, Damien Tournoud, fago, swentel: Switch from Field-based storage to Entity-based storage.

This reverts commit 127b54a6.

Issue #1754246 by webflo, swentel, penyaskito, andypost, alexpott, YesCT, dagmar: Languages should be configuration entities.

Issue #1981342 by aspilicious, andypost, swentel: Drop procedural usage of fields in [s-u-v] modules.

Issue #2004224 by Berdir, andypost: Convert tests using TestEntity to EntityTest (except Field API tests).

Issue #1620010 by dawehner, ParisLiakos, plach, jibran: Move LANGUAGE constants to the Language class.

Issue #1893108 follow-up by Berdir, dawehner: Rename EntityUnitBaseTest => EntityUnitTestBase to conform to coding standards.

Issue #1828790 by plach, chx, pfrenssen: Fixed Entity count query not working with fields shared among different entity types.