Add notice that quality preference doesn't work for YouTube anymore (#726)

package.json

@@ -2,7 +2,7 @@
   "author": "Calvin Montgomery",
   "name": "CyTube",
   "description": "Online media synchronizer and chat",
-  "version": "3.55.2",
+  "version": "3.55.3",
   "repository": {
     "url": "http://github.com/calzoneman/sync"
   },

templates/useroptions.pug

@@ -69,6 +69,7 @@ mixin us-playback
       +rcheckbox("us-synch", "Synchronize video playback")
       +textbox("us-synch-accuracy", "Synch threshold (seconds)", "2")
       +rcheckbox("us-wmode-transparent", "Set wmode=transparent")
+      .form-group
         .col-sm-4
         .col-sm-8
           p.text-info Setting <code>wmode=transparent</code> allows objects to be displayed above the video player, but may cause performance issues on some systems.
@@ -86,6 +87,10 @@ mixin us-playback
             option(value="720") 720p
             option(value="1080") 1080p
             option(value="best") Highest Available
+      .form-group
+        .col-sm-4
+        .col-sm-8
+          p.text-info Due to technical changes on YouTube's side, the CyTube quality preference can no longer be automatically applied on YouTube videos.  See <a href="https://github.com/calzoneman/sync/issues/726" rel="noopener noreferer" target="_blank">this GitHub issue</a> for details.
 
 mixin us-chat
   #us-chat.tab-pane