Issue #2457271 by rteijeiro, Palashvijay4O, Cottser: More cleanup of the 'themeable' documentation group

Issue #2457887 by prateekMehta, stefan.r, rpayanm, alexpott: Use Utility\SafeMarkup class instead of Utility\String for placeholder(), checkPlain(),format() functions

Issue #2303765 by davidhernandez, larowlan, mgifford: Make the default 'alt' attribute for Image fields required

Issue #2273923 by mpdonadio, pfrenssen, effulgentsia, pcambra, xjm, tim.plunkett, martin107, cilefen: Remove html => TRUE option from l() and link generator

Issue #2405469 by yched, googletorp, amateescu, larowlan, Berdir: FileFormatterBase should extend EntityReferenceFormatterBase

Issue #2383165 by sidharrell, alexpott: ResponsiveImageStyle config entities should depend on the image styles they use

Issue #2424697 by jedihe, dalguete, yched: ResponsiveImageFormatter throws an exception on node preview

Revert "Issue #2424697 by jedihe, yched: ResponsiveImageFormatter throws an exception on node preview"

This reverts commit a0d5bc00.

Issue #2260061 by Jelle_S, attiks, Wim Leers, mdrummond, mgifford, holist: Responsive image module does not support sizes/picture polyfill 2.2

Issue #2419857 by Wim Leers, alexpott: Responsive image and View mode schemas should use the config_entity type, can then be simpler

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

Issue #2091321 by er.pushpinderrana, jhodgdon, rootwork, ifrik, mparker17: Update hook_help for Field and Field UI module

Issue #2350837 by dawehner, Berdir, larowlan, Wim Leers: Convert most usages of EntityInterface::getSystemPath() to use routes

Issue #2396687 by hussainweb: Clean-up image module test members - ensure property definition and use of camelCase naming convention

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

Issue #2396715 by hussainweb: Clean-up responsive_image module test members - ensure property definition and use of camelCase naming convention

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

Revert "Issue #2273923 by mpdonadio, pfrenssen, dawehner, xjm, cilefen: Remove html => TRUE option from l() and link generator"

This reverts commit 0bcabf50.

Issue #2273923 by mpdonadio, pfrenssen, dawehner, xjm, cilefen: Remove html => TRUE option from l() and link generator

Issue #2349859 by R. Volk, naxoc: Responsive Image Mappings :: throws a fatal exception if no image style is set

Issue #2378055 by Gábor Hojtsy: Reorganise config schema for entity_form_display / entity_view_display

Issue #2368349 by Gábor Hojtsy, alexpott: Entity view and form display configuration schemas are too verbose / key ones missing

Issue #2322509 by prics, cilefen, gaurav.goyal, harijari, Temoor: Replace all instances of node_load(), node_load_multiple(), entity_load('node') and entity_load_multiple('node') with static method calls.

Issue #2322037 by oenie, Temoor, jepSter, rpayanm: Replace all instances of responsive_image_mapping_load(), entity_load('responsive_image_mapping') and entity_load_multiple('responsive_image_mapping') with static method calls.

Issue #2347465 by tim.plunkett, dawehner, cilefen: Convert all instances of #type link/links to convert to use routes.

Issue #2226207 by lauriii, mgbellaire, Cottser, m1r1k, Mark Carver, LinL, rachel_norfolk, rteijeiro, skwashd, davidhernandez, euphoric_mv: Make 'template' the default output option for hook_theme().

Issue #2343661 by larowlan, tim.plunkett | xjm: Rename l() to _l() and url() to _url(), and document replacements.

Issue #2343651 by xjm, tim.plunkett, Wim Leers, dinarcon, dawehner: Remove most remaining l() calls.

Issue #2342439 by pgautam, joshi.rohit100 | webchick: Some test modules/themes missing Testing package assignment in their info files.