time.Parse - numeric time zones and spacing

<pre>There are two variations of UnixDate that don't parse (and it would make
sense if they did):

1. `Tue Jan 12 02:52:59 -0800 2010` - via ruby's Time.now -- with numeric
time zone

2. `Tue Jan 12 02:43:17 PST 2010` - one space instead of two between Month
and day)</pre>
