Add \versionadded for sftp scheme

Doc/lib/liburlparse.tex

@@ -25,6 +25,7 @@ draft!). It supports the following URL schemes:
 \code{nntp}, \code{prospero}, \code{rsync}, \code{rtsp}, \code{rtspu}, 
 \code{sftp}, \code{shttp}, \code{sip}, \code{snews}, \code{svn}, 
 \code{svn+ssh}, \code{telnet}, \code{wais}.
+\versionadded[Support for the \code{sftp} scheme]{2.5}
 
 The \module{urlparse} module defines the following functions: