Added ability to to show week numbers.
Merge branch 'weeknumbers' of https://github.com/gertsonderby/Pikaday into gertsonderby-weeknumbers
Styled week numbers smaller and gray, removed week header, added example (calendars.html).
Merge branch 'weeknumbers' of https://github.com/gertsonderby/Pikaday into gertsonderby-weeknumbers
Merge #147: Added ability to to show week numbers