Remove Configuration.setValue(); it was unused and untested. (Not needed.)

doc/ZConfig/zconfig.tex

@@ -481,7 +481,7 @@ methods to retrieve information from the section:
 \end{memberdesc}
 
 
-The following methods are used to modify the values defined in a
+The following method is used to modify the values defined in a
 section:
 
 \begin{methoddesc}[Configuration]{addValue}{key, value}
@@ -490,12 +490,6 @@ section:
   raised.
 \end{methoddesc}
 
-\begin{methoddesc}[Configuration]{setValue}{key, value}
-  Set the value for \var{key} to \var{value}.  If there is already a
-  value for \var{key}, it is replaced.  \var{key} and \var{value} must
-  be strings.
-\end{methoddesc}
-
 
 The following methods are used in retrieving and managing sections: