Fixed secure cookie handling

Change-Id: Ice547df6a3a812942eab4707c654d13bfd496fb1
diff --git a/lib/Kalamar.pm b/lib/Kalamar.pm
index 24d57ac..2511e68 100644
--- a/lib/Kalamar.pm
+++ b/lib/Kalamar.pm
@@ -59,7 +59,7 @@
   my $conf = $self->config('Kalamar');
   if ($conf && $conf->{proxy_prefix}) {
 
-    for (app->sessions) {
+    for ($self->sessions) {
       $_->cookie_path($conf->{proxy_prefix});
       $_->cookie_name('kalamar');
       $_->secure(1);