[PATCH] Add --diff-filter= documentation paragraph

Signed-off-by: Jon Loeliger <redacted>

----

So, I don't know what the "*" selection flag does.
It is called "AON" in the source.  Anyone?

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index 5c85167..e00dd6c 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt

@@ -35,6 +35,13 @@
 -C::

	Detect copies as well as renames.

+--diff-filter=[ACDMRTUX*B]::
+	Select only files that are Added (A), Copied (C), Deleted (D),
+	Modified (M), Renamed (R), have their Type (mode) changed,
+	are Unmerged (U), are Unknown (X), are "AON" (*),
+	or have had their pairing Broken (B).  Any combination of
+	the filter characters may be used.
+
 --find-copies-harder::
	For performance reasons, by default, -C option finds copies only
	if the original file of the copy was modified in the same