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.Client/Chat/SpeechBubble.cs

@@ -5,7 +5,6 @@ using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Maths;
-using Robust.Shared.Timers;
 using Robust.Shared.Timing;
 
 namespace Content.Client.Chat