Launch autoRefreshLists feature

This CL promotes the feature from an experiment to an option, and adds
the docs for the feature.

Fixed: twpowertools:25
Change-Id: Ic9a37298b1d1fe4b6c0d4810ecb03253392f456c
diff --git a/src/options/optionsPage.json5 b/src/options/optionsPage.json5
index 9647dd6..9f6e7fd 100644
--- a/src/options/optionsPage.json5
+++ b/src/options/optionsPage.json5
@@ -27,6 +27,7 @@
         {codename: 'enhancedannouncementsdot'},
         {codename: 'repositionexpandthread', experimental: true},
         {codename: 'threadlistavatars'},
+        {codename: 'autorefreshlist'},
       ],
     },
     {