Define CVars in a central location.

Instead of a bunch of RegisterCVar<> calls, it's now similar to Key Functions.

Content.Shared/CCVars.cs

@@ -0,0 +1,25 @@
+using Robust.Shared;
+using Robust.Shared.Configuration;
+
+namespace Content.Shared
+{
+    // ReSharper disable once InconsistentNaming
+    [CVarDefs]
+    public sealed class CCVars : CVars
+    {
+        public static readonly CVarDef<bool>
+            GameLobbyEnabled = CVarDef.Create("game.lobbyenabled", false, CVar.ARCHIVE);
+
+        public static readonly CVarDef<int>
+            GameLobbyDuration = CVarDef.Create("game.lobbyduration", 20, CVar.ARCHIVE);
+
+        public static readonly CVarDef<string>
+            GameLobbyDefaultPreset = CVarDef.Create("game.defaultpreset", "Suspicion", CVar.ARCHIVE);
+
+        public static readonly CVarDef<string>
+            GameLobbyFallbackPreset = CVarDef.Create("game.fallbackpreset", "Sandbox", CVar.ARCHIVE);
+
+        public static readonly CVarDef<bool>
+            GameLobbyEnableWin = CVarDef.Create("game.enablewin", true, CVar.ARCHIVE);
+    }
+}