[PATCH] Document the delta attribute

After spending a bit of time searching through the pack-objects source
I figured a small blurb of text documenting the existence of this attribute
would be useful.

Feel free to enhance/improve/correct the text.

Nasser

Signed-off-by: Nasser Grainawi <redacted>
---
  Documentation/gitattributes.txt |   10 ++++++++++
  1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index 1195e83..132e7b3 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt

@@ -577,6 +577,16 @@ If this attribute is not set or has an invalid value, the 

value of the
  (See linkgit:git-config[1]).


+Packing objects
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+`delta`
+^^^^^^^^^^
+
+Delta compression will not be attempted for files and directories with
+the attribute `delta` unset.
+
+
  USING ATTRIBUTE MACROS
  ----------------------

-- 
1.6.5