[PATCH] Improve documentation for --dirstat diff option

[Heikki Orsila <heikki.orsila@iki.fi>]

Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
---
My earlier version of the patch already gave an example of use. This 
version changes the word "damage" to "impact" (Jakub Narebski's 
suggestion).

 Documentation/diff-options.txt |   11 +++++------
 1 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index 1759386..150debb 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -59,12 +59,11 @@ endif::git-format-patch[]
 	lines.
 
 --dirstat[=limit]::
-	Output only the sub-directories that are impacted by a diff,
-	and to what degree they are impacted.  You can override the
-	default cut-off in percent (3) by "--dirstat=limit".  If you
-	want to enable "cumulative" directory statistics, you can use
-	the "--cumulative" flag, which adds up percentages recursively
-	even when they have been already reported for a sub-directory.
+	Output the distribution of relative impact (number of lines added or
+	removed) for each sub-directory. Directories with impact below
+	a cut-off percent (3% by default) are not shown. The cut-off percent
+	can be set with "--dirstat=limit". Child directory impact is not
+	counted for the parent directory, unless "--cumulative" is used.
 
 --summary::
 	Output a condensed summary of extended header information
-- 
1.6.0.1