PauseManager moved to Shared (#3288)

* Namespace changes for moving IPauseManager to shared.

* Namespace changes for moving ITimerManager from Timers to Timing.

* Rebase Fixes.

* Update engine submodule to v0.3.8

Content.Server/GameObjects/EntitySystems/AtmosphereSystem.cs

@@ -1,4 +1,4 @@
-#nullable enable
+#nullable enable
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -11,13 +11,13 @@ using Content.Shared.GameObjects.EntitySystems.Atmos;
 using Content.Shared.Maps;
 using JetBrains.Annotations;
 using Robust.Server.GameObjects;
-using Robust.Server.Timing;
 using Robust.Shared.Configuration;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
 using Robust.Shared.Maths;
 using Robust.Shared.Prototypes;
+using Robust.Shared.Timing;
 
 namespace Content.Server.GameObjects.EntitySystems
 {