Themes: Document the new theme features being added.

The `add_theme_support()` inline docs now includes the features that the block editor adds.

Props desrosj.
See #45134.


Built from https://develop.svn.wordpress.org/branches/5.0@43814


git-svn-id: http://core.svn.wordpress.org/branches/5.0@43643 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/theme.php

@@ -2210,7 +2210,9 @@ function get_theme_starter_content() {
  * @since 4.1.0 The `title-tag` feature was added
  * @since 4.5.0 The `customize-selective-refresh-widgets` feature was added
  * @since 4.7.0 The `starter-content` feature was added
- * @since 5.0.0 The `responsive-embeds` feature was added.
+ * @since 5.0.0 The `responsive-embeds`, `align-wide`, `dark-editor-style`, `disable-custom-colors`,
+ *              `disable-custom-font-sizes`, `editor-color-pallete`, `editor-font-sizes`,
+ *              `editor-styles`, and `wp-block-styles` features were added.
  *
  * @global array $_wp_theme_features
  *

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-alpha-43813';
+$wp_version = '5.0-alpha-43814';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.