Fixed a few warnings.

modules/UNO.pm

@@ -927,6 +927,7 @@ sub _runcard {
                     # Delete all the cards.
                     my $delres;
                     foreach (@xcards) { $delres = _delcard($CURRTURN, $_); }
+                    if (defined $delres) {
                         my $str;
                         for (my $i = $#xcards; $i >= 0; $i--) { $str .= ' '._fmtcard($xcards[$i]); }
                         $str = substr $str, 1;
@@ -935,6 +936,8 @@ sub _runcard {
                             _nextturn(0); 
                         }
                     }
+                    else { _nextturn(0); }
+                }
                 when ('T') {
                     # Get cards.
                     my @ucards = @{$PLAYERS{$CURRTURN}};