Add urls.txt to git-clone man page

Since git-clone is one of the many commands taking
URLs to remote repositories as an argument, it should include
the URL-types list from urls.txt.

Split up urls.txt into urls.txt and urls-remotes.txt.  The latter
should be used by anything besides git-clone where a discussion of
using .git/config and .git/remotes/ to name URLs just doesn't make
as much sense.

Signed-off-by: Andrew Ruder <andy@aeruder.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt
index 4a5bab5..2f39864 100644
--- a/Documentation/git-clone.txt
+++ b/Documentation/git-clone.txt
@@ -106,8 +106,9 @@
 	as patches.
 
 <repository>::
-	The (possibly remote) repository to clone from.  It can
-	be any URL git-fetch supports.
+	The (possibly remote) repository to clone from.  See the
+	<<URLS,URLS>> section below for more information on specifying
+	repositories.
 
 <directory>::
 	The name of a new directory to clone into.  The "humanish"
@@ -116,6 +117,8 @@
 	for "host.xz:foo/.git").  Cloning into an existing directory
 	is not allowed.
 
+include::urls.txt[]
+
 Examples
 --------