* Identity.cs: Added ObjRef attribute, that holds the objref of the object.

	* Identity.cs: Added ObjRef attribute, that holds the objref of the object.
	  Removed implementation of CreateObjRef. Now it is implemented in the derived classes.
	* ServerIdentity.cs: Added implementation of CreateObjRef.
	* RemotingServices.cs: Changed implementation of GetRemoteObject and GetClientIdentity.
	  Now they only have and ObjRef as input parameter. This is the objref received from
	  the server. Unmarshal() also checks if the objref is for a well known object.
	  In this case, a proxy is always created, but if not, it tries to get the real object.
	* ObjRef.cs: Added some flags that have info for marshalling/unmarshalling.
	  Changed behavior of IsPossibleToCAD. Now returns false. Returning true makes serialization
	  of this ObjRef to fail in the target AD. Added method UpdateChannelInfo.

svn path=/trunk/mcs/; revision=11292