Re: bug and fix for `dired-do-copy

[Francesco Potorti`]

   I think I tried to make a feeble attempt at helping the user find out
   what the problem is by checking for an error situation and then
   showing the *rcp* buffer to the user.  But that doesn't seem to be
   very helpful -- in most cases where people had problems, the buffer
   was empty :-(

Always create a debug buffer (get rid of rcp-debug-buffer) and show that
one.  That's what ange-ftp does.