Adds some missing versionadded in settings docs.

docs/advanced_topics/settings.rst

@@ -233,6 +233,8 @@ To use Embedly, you must also install their Python module:
 Dashboard
 ---------
 
+.. versionadded:: 1.10
+
 .. code-block:: python
 
     WAGTAILADMIN_RECENT_EDITS_LIMIT = 5
@@ -330,6 +332,8 @@ Tags are case-sensitive by default ('music' and 'Music' are treated as distinct
 Multi-word tags
 ---------------
 
+.. versionadded:: 1.10
+
 .. code-block:: python
 
   TAG_SPACES_ALLOWED = False
@@ -348,6 +352,8 @@ By default, page slugs can contain any alphanumeric characters, including non-La
 Auto update preview
 -------------------
 
+.. versionadded:: 1.10
+
 .. code-block:: python
 
   WAGTAIL_AUTO_UPDATE_PREVIEW = False
@@ -412,6 +418,8 @@ Specifies the date and datetime format to be used in input fields in the Wagtail
 Admin languages
 ---------------
 
+.. versionadded:: 1.10
+
 Users can choose between several languages for the admin interface
 in the account settings. The list of languages is by default all the available
 languages in Wagtail. To change it, set ``WAGTAILADMIN_PERMITTED_LANGUAGES``: