Documentation/gitdiffcore: Remove misleading date in heading

Ever since the automatic conversion into man form, the heading
contained a misidentified subheading reading "June 2005".
Remove this since the documentation is more recent, and the correct
date is in the footer.

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/gitdiffcore.txt

diff --git a/Documentation/gitdiffcore.txt b/Documentation/gitdiffcore.txt
index e8041bc..3cd21b6 100644
--- a/Documentation/gitdiffcore.txt
+++ b/Documentation/gitdiffcore.txt
@@ -3,7 +3,7 @@
 
 NAME
 ----
-gitdiffcore - Tweaking diff output (June 2005)
+gitdiffcore - Tweaking diff output
 
 SYNOPSIS
 --------