Issue #2444231 by Wim Leers, nlisgo: Fix CacheableInterface so it makes sense (was: "Make Config objects & Entities implement CacheableInterface + add BubbleableMetadata::createFromCacheableObject()")

Issue #2212069 by Gábor Hojtsy, pjonckiere, rteijeiro, cilefen: Non-English Drupal sites get default configuration in English, edited in English, originals not actually used if translated

Revert "Revert "Issue #2457653 by Gábor Hojtsy: System.site langcode is both used as a file language code and a site language code""

This reverts commit 079a52b4.

Revert "Issue #2457653 by Gábor Hojtsy: System.site langcode is both used as a file language code and a site language code"

This reverts commit 364a6e9c.

Issue #2457653 by Gábor Hojtsy: System.site langcode is both used as a file language code and a site language code

Issue #356399 by dawehner, beejeebus, catch, sidharrell, klausi, nlisgo, Josh Waihi, Berdir, martin107: Optimize the route rebuilding process to rebuild on write

Issue #2423153 by idebr, dawehner, Frankencio: Add menu from the editing page doesn't save the changes

Issue #2418017 by Wim Leers, YesCT, dawehner, webchick, jibran, amateescu, hussainweb: Implement autocomplete UI for the link widget

Issue #2417647 by Wim Leers, effulgentsia: Add leading slash to paths within 'user-path:' URIs, to allow 'user-path:' URIs to point to the <none> route

Issue #2406103 by Berdir, alexpott: Remove hook_node_validate() and hook_node_submit() because they bypass the entity API

Issue #2349071 by Upchuk, Cottser, pwolanin: EntityStorageException when trying to save a link over the maximum depth

Issue #2396699 by hussainweb, sivaji@knackforge.com: Clean-up menu_ui module test members - ensure property definition and use of camelCase naming convention

Issue #2417645 by tim.plunkett, effulgentsia, pwolanin: Change destination query string handling to break dependence on system path

Issue #2417793 by effulgentsia, Wim Leers, YesCT, yched, dawehner: Allow entity: URIs to be entered in link fields

Issue #2416955 by dawehner, YesCT, amateescu, jibran, yched, anavarre: Convert MenuLinkContent to use a link widget

Issue #2417333 by Wim Leers, pwolanin, xjm, dawehner: Add support for user-path: scheme to Url class

Issue #2406749 by dawehner, YesCT, amateescu, hussainweb, kim.pepper, RavindraSingh, pwolanin, Wim Leers, Gábor Hojtsy, yched, jibran: Use a link field for custom menu link

Issue #1728804 by Berdir: Introduce (Content)EntityDeleteForm and children to handle entity deletions

Issue #2040135 by Wim Leers, Berdir: Caches dependent on simple config are only invalidated on form submissions

Issue #2281645 by dawehner, andypost: Make entity annotations use link templates instead of route names

Issue #2309737 by rpayanm, hussainweb, max-kuzomko, herom, millerbennett, ianthomas_uk, quietone, Sutharsan, sumitmadan, toddmbloom: Remove deprecated format_plural usage

Issue #2294157 by tim.plunkett, dawehner: Switch getOptions() and getRouteParameters() within LocalActionInterface and LocalTaskInterface to use RouteMatch