Issue #1965208 by amateescu, Berdir: Convert TaxonomyTermReferenceItem to extend EntityReferenceItem.
Issue #1981342 by aspilicious, andypost, swentel: Drop procedural usage of fields in [s-u-v] modules.
Issue #1818560 by Berdir, fago, Wim Leers, jessebeach, dawehner, YesCT: Convert taxonomy entities to the new Entity Field API.
Issue #1893108 follow-up by Berdir, dawehner: Rename EntityUnitBaseTest => EntityUnitTestBase to conform to coding standards.
Issue #1801304 by Amitaibu, amateescu, effulgentsia, tim.plunkett, EclipseGc, Fabianx, Cottser: Added Entity reference field.
Issue #1552396 by andypost, sun, tim.plunkett, amateescu, YesCT: Convert vocabularies into configuration.