Documentation/git-remote-helpers: explain how import works with multiple refs

This is important for two reasons:

* when two "import" lines follow each other, only one "done" command
  should be issued in the fast-import stream, not one per "import".

* The blank line terminating an import command should not be confused
  with the one terminating the sequence of commands.

While we're there, illustrate the corresponding explanation for push
batches with an example.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-remote-helpers.txt

@@ -241,7 +241,22 @@ Supported if the helper has the "fetch" capability.
 'push' +<src>:<dst>::
 	Pushes the given local <src> commit or branch to the
 	remote branch described by <dst>.  A batch sequence of
-	one or more push commands is terminated with a blank line.
+	one or more 'push' commands is terminated with a blank line
+	(if there is only one reference to push, a single 'push' command
+	is followed by a blank line). For example, the following would
+	be two batches of 'push', the first asking the remote-helper
+	to push the local ref 'master' to the remote ref 'master' and
+	the local 'HEAD' to the remote 'branch', and the second
+	asking to push ref 'foo' to ref 'bar' (forced update requested
+	by the '+').
++
+------------
+push refs/heads/master:refs/heads/master
+push HEAD:refs/heads/branch
+\n
+push +refs/heads/foo:refs/heads/bar
+\n
+------------
 +
 Zero or more protocol options may be entered after the last 'push'
 command, before the batch's terminating blank line.
@@ -266,6 +281,11 @@ Supported if the helper has the "push" capability.
 Especially useful for interoperability with a foreign versioning
 system.
 +
+Just like 'push', a batch sequence of one or more 'import' is
+terminated with a blank line. For each batch of 'import', the remote
+helper should produce a fast-import stream terminated by a 'done'
+command.
++
 Supported if the helper has the "import" capability.
 
 'connect' <service>::