Issue #2776975 by joelpittet, dawehner, tim.plunkett, xjm, pfrenssen: March 3, 2017: Convert core to array syntax coding standards for Drupal 8.3.x RC phase

Issue #2324371 by lauriii, aneek, chx, joelpittet, webflo, Fabianx, rteijeiro: Fix common HTML escaped render #key values due to Twig autoescape.

Issue #2028109 by tim.plunkett, almaudoh, twistor, larowlan, slashrsm, Berdir, Arla, neclimdul, Cottser: Convert hook_stream_wrappers() to tagged services.

Issue #2309175 by Wim Leers: Fixed HTML double-escaping in Text Editor image settings configuration UI.

Issue #2030605 by tim.plunkett, mr.baileys, webwarrior, Wim Leers | plopesc: Expand Editor with methods.

Issue #2130811 by alexpott, Gábor Hojtsy, vijaycs85, sun, Wim Leers: Use config schema in saving and validating configuration form to ensure data is consistent and correct.

Issue #2105939 by Wim Leers, vijaycs85: Make sure all YML files in Editor module has no type-casting to string + config system changes broke image uploading in editors.

Issue #2067119 by pameeela, longwave, tstoeckler, Wim Leers: Fixed 'width' and 'height' HTML placeholder attributes in image dialog are not translated, yet should be lcfirst.

Issue #1932652 by Wim Leers, nirbhasa, quicksketch: Add image uploading to WYSIWYGs through editor.module.