Issue #437: Change page title when layout overridden.
Merge pull request #579 from BWPanda/437/page-title-override

Issue #437: Change page title when layout overridden.
Issue 453: Fixing backwards-compatibility mode for Drupal behaviors.
Merge pull request #586 from quicksketch/453/fix_drupal_js

Issue 453: Fixing backwards-compatibility mode for Drupal behaviors.
Issue #455: Sort options alphabetically when exporting configuration.
Issue #456: Remove rogue calls to drupal_* functions in core.
Merge pull request #588 from quicksketch/456/update_drupal_calls

Issue #456: Remove rogue calls to drupal_* functions in core.
Merge pull request #587 from quicksketch/455/sort_config_export

Issue #455: Sort options alphabetically when exporting configuration.
Issue #450: Remove regions defaults from _system_rebuild_theme_data().
Issue #450: Removing backdrop_set_page_content() and remaining region references.