Display current voting identifier in menu.

Add a header line with the identifier (name)
of the currently processed voting to the menu
display by UVmenu so one can check whether
the ballot really belongs to the current voting
even when checking more than one voting in a
batch.

Signed-off-by: Thomas Hochstein <thh@inter.net>

UVmenu.pm

@@ -60,6 +60,7 @@ sub menu {
   while (1) {
 
     system($config{clearcmd});
+    print "-> $config{votename} <-\n";
     print UVmessage::get("MENU_PROBLEMS") . "\n";
 
     foreach my $error (keys %errors) {