Preserve attachment point & position when attachment is rezzed in world

Patch taken from
http://opensimulator.org/mantis/view.php?id=4905
originally by Greg C.

Fixed to apply to r/23314 commit
ba9daf849e
(cherry picked from commit 4ff9fbca441110cc2b93edc7286e0e9339e61cbe)

OpenSim/Region/ClientStack/Linden/Caps/ObjectCaps/UploadObjectAssetModule.cs

@@ -277,6 +277,7 @@ namespace OpenSim.Region.ClientStack.Linden
                 pbs.ProfileEnd = (ushort) obj.ProfileEnd;
                 pbs.Scale = obj.Scale;
                 pbs.State = (byte) 0;
+                pbs.LastAttachPoint = (byte) 0;
                 SceneObjectPart prim = new SceneObjectPart();
                 prim.UUID = UUID.Random();
                 prim.CreatorID = AgentId;