Fix SF bug 568269 by enclosing 'computername' in a raw string

Doc/lib/libwinreg.tex

@@ -36,7 +36,7 @@ This module offers the following functions:
   another computer, and returns a \dfn{handle object}
 
  \var{computer_name} is the name of the remote computer, of the 
- form \samp{\e\e computername}.  If \code{None}, the local computer
+ form \code{"r\e\e computername"}.  If \code{None}, the local computer
  is used.
  
  \var{key} is the predefined handle to connect to.