[PATCH] Documentation: describe diff tweaking (fix).

I cannot count ;-)

Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/diffcore.txt

@@ -45,7 +45,7 @@ the -p option is not used.  E.g.
 The diffcore mechanism is fed a list of such comparison results
 (each of which is called "filepair", although at this point each
 of them talks about a single file), and transforms such a list
-into another list.  There are currently 7 such transformations:
+into another list.  There are currently 6 such transformations:
 
  - diffcore-pathspec
  - diffcore-break