Added subscription to handler list so subscription can be accessed from handler.

TCPSession.h

@@ -78,7 +78,7 @@ namespace core
     ///
     /// alias is a void pointer that can be set to point to any object that identifies
     /// this session uniquely. Using this approach, inheriting objects can determine
-    /// how it knows the contacts that this server manages. 
+    /// how it knows the contacts that this server manages.
     ///
 
     void *alias;