Views added to core

Views module was installed in over 70% of Drupal sites. Views is now part of Backdrop core.

Significant changes

• CTools "autosubmit" is now a library, "backdrop.autosubmit" provided by system.module.
• CTools "jumpmenu" is now a library and form callback provided by system.module. Previously CTools jump menus would be generated with the function ctools_jumpmenu_form(). In Backdrop this is system_jump_menu().
• CTools ctools_math_expr has been renamed to its original library name EvalMath and included in core/includes/evalmath.inc.
• CTools #dependency form API properties have been removed in preference of the #states property provided by core.
• Views previously utilized CTools plugins for providing "Views wizards" for creating new views. This has been replaced with a hook, hook_views_ui_wizards.
• hook_views_default_views() has been removed in favor of the config system. Modules needing to provide their own views should include the view as a default config file. See the Comment module for an example: views.view.comments_recent.json

And some other obvious changes that aren't really API changes, but significant:

• Views now uses the config system for variables
• Views now uses the config system for saving, loading, reverting, and cloning views
• Implementations of various fields, filters, sorts, etc. have been moved to individual modules instead of being grouped all together in views module directory.

Administrative listings are also converted to use views rather than legacy code. See https://github.com/backdrop/backdrop-issues/issues/151 for a list of conversions.