Resolve fix:

- CancelResolv(): Standard function to cancel name resolve requests
  - Allow Resolv request to complete if not cancelled
  - Clear memory if resolve request cancelled
- getaddrinfo_a(): still leaks if thread not closed
Other:
- Code clean up

SelectableCore.h

@@ -313,6 +313,7 @@ protected:
     // Socket Operations
     bool    ResolveAddress( THandle * Handle );
     bool    HandleResolve( THandle * Handle );
+    bool    CancelResolve( THandle * Handle );
     bool    DestroyResolveReq( THandle * Handle, bool DestroyResult );
 
     // Managing File Handles