v.buffer manual: link to v.parallel

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@59534 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.buffer/v.buffer.html

@@ -86,6 +86,7 @@ shown in black)
 
 <em>
 <a href="r.buffer.html">r.buffer</a>,
+<a href="v.parallel.html">v.parallel</a>,
 <a href="v.extract.html">v.extract</a>,
 <a href="v.type.html">v.type</a>,
 <a href="v.patch.html">v.patch</a>,