TODO

Required for release:
 1. Cross browser issues, status:
     - Firefox: Performance sluggish, see below
 2. Internationalization. Mostly done, but
     - date preview in picker is always full month, day, full year (which actually looks fine, but goes against the Android implementation)

Would be nice:
 - Optional: Snap-to-month effect
 - Infinite scrolling now works through the 'official' polymer template way, which
   comes at a huge performance penalty. In chrome this is still super quick,
   IE11 is acceptable, FF however it is downright sluggish. There is an open issue
   on Github which would definitely help make this faster:
    https://github.com/Polymer/TemplateBinding/issues/204
 
Done:
 - Cleaning up of code
 - Write docs
 - Min & Max date
 - Mobile per year selection (infinite scrolling works imperfectly on mobile)
 - immediateDate vs date (only after hitting OK the date should be set)
 - Got everything working cross browser
 - first day of week is now a property, not based on locale