CSS and JS resources throw ArgumentOutOfRangeException

I just pulled down the latest version of hangfire and was experiencing the issue mentioned in #125, this change will fix that issue.  I'm not entirely sure, but I believe it has to do with timezones, and using DateTime.MaxValue, and so when the time is converted to UTC, it gets an ArgumentOutOfRangeException since the year is now greater then 10,000.  This pull request just changes the expiry date to 1 year out which should be good.