Add a version annotation for splitdrive(); old, but as long as I managed

to end up with the information, it is better recorded than lost.

Doc/lib/libposixpath.tex

@@ -181,6 +181,7 @@ Split the pathname \var{path} into a pair \code{(\var{drive},
 empty string.  On systems which do not use drive specifications,
 \var{drive} will always be the empty string.  In all cases,
 \code{\var{drive} + \var{tail}} will be the same as \var{path}.
+\versionadded{1.3}
 \end{funcdesc}
 
 \begin{funcdesc}{splitext}{path}