fix bug and #40 (again)

added one commit and two tests.

```
	testMinute: function() { with(this) {
		assertEqual('3', $.format.date('Wed Jan 09 06:3:38 PST 2012', 'm'));
		assertEqual('03', $.format.date('Wed Jan 09 06:3:38 PST 2012', 'mm'));
		assertEqual('Apr 17 2013 10:08:01', $.format.date("2013-04-17 10:8:1", "MMM dd yyyy HH:mm:ss"));
	}},
	testSecond: function() { with(this) {
		assertEqual('8', $.format.date('Wed Jan 09 06:3:8 PST 2012', 's'));
		assertEqual('08', $.format.date('Wed Jan 09 06:3:8 PST 2012', 'ss'));
	}},
```

haha