Typo
Neaten `updatePeriod` function slightly.
Add weekend days to `Locale`. See `isWeekend(day)` function.
New disable mixins. Applicable to both dates and times.

- Calendar.DisablePast for any selection before Date.now()
- Calendar.DisableFuture for any after Date.now()
- Calendar.DisableWeekends compares against Locale#isWeekend(day)
- Calendar.DisableWeekdays inverse of DisableWeekends
Make widgets unselectable.
Remove styles for Rails, version 2 is incompatible anyway.
Make calendar title a drag handle, show appropriate cursor.
Added `weekend` class to day cells for styling. Sample rule provided.
Move `firstDayOfWeek` to `Locale`.