Documentation: fix git-clone manpage not to refer to itself

Signed-off-by: Sergei Organov <osv@javad.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-clone.txt

@@ -130,6 +130,7 @@ OPTIONS
 	for "host.xz:foo/.git").  Cloning into an existing directory
 	is not allowed.
 
+:git-clone: 1
 include::urls.txt[]
 
 Examples

Documentation/urls.txt

@@ -36,5 +36,11 @@ To sync with a local directory, you can use:
 - file:///path/to/repo.git/
 ===============================================================
 
+ifndef::git-clone[]
 They are mostly equivalent, except when cloning.  See
 gitlink:git-clone[1] for details.
+endif::git-clone[]
+
+ifdef::git-clone[]
+They are equivalent, except the former implies --local option.
+endif::git-clone[]