Issue #2888763 by Graber, skyredwang, borisson_, Wim Leers, tstoeckler, e0ipso, dawehner: DecimalItem should not use String as its DataDefinition

Issue #2851394 by GoZ, hgunicamp, oknate, jungle, wolffereast, tameeshb, mmatsoo, ridhimaabrol24, jofitz, swarad07, tanc, shaktik, dimaro, shashikant_chauhan, MerryHamster, quietone, nitesh624, martin_q, boaloysius, gaurav.kapoor, nitvirus, ankithashetty, Munavijayalakshmi, kostyashupenko, leolando.tan, amit.drupal, ravi.shankar, akashkrishnan01, Swapnil_Kotwal, Saviktor, mrinalini9, anmolgoyal74, Venkatesh Rajan.J, shimpy, lomasr, Dinesh18, shubham.prakash, mahtab_alam, markdorison, cilefen, longwave, bleen, xjm, alexpott, gmaltoni: Fix grammar 'a' to 'an' when necessary

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

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

Issue #1969728 by yched, effulgentsia, swentel, fago, plach: Implement Field API 'field types' as TypedData Plugins.

Issue #1777956 by fago, klausi, sun, dasjo: Provide a way to define default values for entity fields.

Issue #1839080 by Berdir, fago, dasjo, jjchinquist: Implement the new entity field API for the link field type.

Issue #1818556 by das-peter, plach, fago, Berdir, vijaycs85: Change notice: Convert nodes to the new Entity Field API.

Issue #1845546 by fago, EclipseGc, attiks, effulgentsia: Implement validation for the TypedData API.

Issue #1877632 by fago, jhodgdon: Improve comments and clean-up code for EntityNG and the TypedData API.

Issue #1839078 by dasjo, tim.plunkett, fago: Implement the new entity field API for the email field type.

Issue #1869250 by fago, Berdir, das-peter, YesCT, mradcliffe, fubhy: Various EntityNG and TypedData API improvements.

Issue #1696640 by fago, effulgentsia, tim.plunkett, dixon_, plach: Add a uniform Entity Property API.