Rework options menu.

It's much nicer now.

Content.Client/UserInterface/OptionsMenu.Audio.cs

@@ -0,0 +1,21 @@
+using Robust.Client.Interfaces.ResourceManagement;
+using Robust.Client.UserInterface;
+using Robust.Shared.Interfaces.Configuration;
+using Robust.Shared.IoC;
+
+namespace Content.Client.UserInterface
+{
+    public sealed partial class OptionsMenu
+    {
+        private sealed class AudioControl : Control
+        {
+            public AudioControl(IConfigurationManager cfg)
+            {
+                AddChild(new Placeholder(IoCManager.Resolve<IResourceCache>())
+                {
+                    PlaceholderText = "Pretend there's a bunch of volume sliders here."
+                });
+            }
+        }
+    }
+}