Core/Game: Converted the game library to a shared library.

* There is still the possibility to static link against game.

(cherry picked from commit bf33159a70)

src/server/game/Scripting/ScriptSystem.h

@@ -45,7 +45,7 @@ struct ScriptPointMove
 
 typedef std::vector<ScriptPointMove> ScriptPointVector;
 
-class SystemMgr
+class TC_GAME_API SystemMgr
 {
     private:
         SystemMgr() { }