Documentation/git-commit.txt: describe --dry-run

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-commit.txt

@@ -9,7 +9,7 @@ SYNOPSIS
 --------
 [verse]
 'git commit' [-a | --interactive] [-s] [-v] [-u<mode>] [--amend] [--dry-run]
-	   [(-c | -C) <commit>] [-F <file> | -m <msg>]
+	   [(-c | -C) <commit>] [-F <file> | -m <msg>] [--dry-run]
 	   [--allow-empty] [--no-verify] [-e] [--author=<author>]
 	   [--cleanup=<mode>] [--] [[-i | -o ]<file>...]
 
@@ -42,10 +42,9 @@ The content to be added can be specified in several ways:
    by one which files should be part of the commit, before finalizing the
    operation.  Currently, this is done by invoking 'git-add --interactive'.
 
-The 'git-status' command can be used to obtain a
+The `--dry-run` option can be used to obtain a
 summary of what is included by any of the above for the next
-commit by giving the same set of parameters you would give to
+commit by giving the same set of parameters (options and paths).
-this command.
 
 If you make a commit and then find a mistake immediately after
 that, you can recover from it with 'git-reset'.
@@ -70,6 +69,12 @@ OPTIONS
 	Like '-C', but with '-c' the editor is invoked, so that
 	the user can further edit the commit message.
 
+--dry-run::
+	Do not actually make a commit, but show the list of paths
+	with updates in the index, paths with changes in the work tree,
+	and paths that are untracked, similar to the one that is given
+	in the commit log editor.
+
 -F <file>::
 --file=<file>::
 	Take the commit message from the given file.  Use '-' to