Moved the SetupScene methods from RegionApplicationBase to OpenSimBase [Do we really still need RegionApplicationBase?]

Added a flag (bool m_autoCreateLindenStack = true) which says if the ClientStack will be autocreated and initialised when creating regions. This helps with moving ClientStacks to Region modules. 
Currently this flag is hardcoded to true, as it is only for testing at the moment, so you need to change the value in the code if you want to turn off auto creating.

OpenSim/Framework/RegionInfo.cs

@@ -208,6 +208,7 @@ namespace OpenSim.Framework
         public string MasterAvatarSandboxPassword = String.Empty;
         public UUID originRegionID = UUID.Zero;
         public string proxyUrl = "";
+        public int ProxyOffset = 0;
         public string RegionName = String.Empty;
         public string regionSecret = UUID.Random().ToString();