[PATCH] Document git-ls-files --directory

Add the appropriate bit of documentation.

I did not review GIT patches for missing documentation updates during
Christmas and around the New Year, but I guess that I will have to start
again. ;-)

Signed-off-by: Petr Baudis <redacted>
---

 Documentation/git-ls-files.txt |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/Documentation/git-ls-files.txt b/Documentation/git-ls-files.txt
index e42af5e..e433407 100644
--- a/Documentation/git-ls-files.txt
+++ b/Documentation/git-ls-files.txt

@@ -46,6 +46,10 @@ OPTIONS
 -s|--stage::
 	Show stage files in the output
 
+--directory::
+	If a whole directory is classified as "other", show just its
+	name (with a trailing slash) and not its whole contents.
+
 -u|--unmerged::
 	Show unmerged files in the output (forces --stage)