gitweb: only display "next" links in logs if there is a next page

There was a bug in the implementation of the "next" links in
format_paging_nav (for log and shortlog), which caused the next links
to always be displayed, even if there is no next page.  This fixes it.

Signed-off-by: Lea Wiemann <LeWiemann@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 12843a4..345acf4 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -2676,7 +2676,7 @@
 }
 
 sub format_paging_nav {
-	my ($action, $hash, $head, $page, $nrevs) = @_;
+	my ($action, $hash, $head, $page, $has_next_link) = @_;
 	my $paging_nav;
 
 
@@ -2694,7 +2694,7 @@
 		$paging_nav .= " &sdot; prev";
 	}
 
-	if ($nrevs >= (100 * ($page+1)-1)) {
+	if ($has_next_link) {
 		$paging_nav .= " &sdot; " .
 			$cgi->a({-href => href(-replay=>1, page=>$page+1),
 			         -accesskey => "n", -title => "Alt-n"}, "next");
@@ -4585,7 +4585,7 @@
 
 	my @commitlist = parse_commits($hash, 101, (100 * $page));
 
-	my $paging_nav = format_paging_nav('log', $hash, $head, $page, (100 * ($page+1)));
+	my $paging_nav = format_paging_nav('log', $hash, $head, $page, $#commitlist >= 100);
 
 	git_header_html();
 	git_print_page_nav('log','', $hash,undef,undef, $paging_nav);
@@ -5505,7 +5505,7 @@
 
 	my @commitlist = parse_commits($hash, 101, (100 * $page));
 
-	my $paging_nav = format_paging_nav('shortlog', $hash, $head, $page, (100 * ($page+1)));
+	my $paging_nav = format_paging_nav('shortlog', $hash, $head, $page, $#commitlist >= 100);
 	my $next_link = '';
 	if ($#commitlist >= 100) {
 		$next_link =