gitweb: Make the Git logo link target to point to the homepage

It provides more useful information for causual Git users than the Git docs
(especially about where to get Git and such).

People can override with GITWEB_CONFIG if they want to.

Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Acked-by: Petr Baudis <pasky@suse.cz>
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 8bf7bf4..3320069 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -51,6 +51,9 @@
 # URI of GIT favicon, assumed to be image/png type
 our $favicon = "++GITWEB_FAVICON++";
 
+our $githelp_url = "http://git.or.cz/";
+our $githelp_label = "git homepage";
+
 # source of projects list
 our $projects_list = "++GITWEB_LIST++";
 
@@ -1373,7 +1376,9 @@
 	print "</head>\n" .
 	      "<body>\n" .
 	      "<div class=\"page_header\">\n" .
-	      "<a href=\"http://www.kernel.org/pub/software/scm/git/docs/\" title=\"git documentation\">" .
+	      "<a href=\"" . esc_html($githelp_url) .
+	      "\" title=\"" . esc_html($githelp_label) .
+	      "\">" .
 	      "<img src=\"$logo\" width=\"72\" height=\"27\" alt=\"git\" style=\"float:right; border-width:0px;\"/>" .
 	      "</a>\n";
 	print $cgi->a({-href => esc_url($home_link)}, $home_link_str) . " / ";