* fixed bug where date was not being forced between startDate and endDate
* added tests for bug fix above
Take scroll into account when calculating overflows for orientation
Slight tweak to placement calculations
Add utility functions for converting between UTC and local dates
Give local dates to beforeShowDay callback

Closes #526
Performance improvement for beforeShowDay not being provided
Fix bug where startDate and endDate specified dates were not themselves selectable

Fixes #330, #485
Fix options test suite cleanup
Merge pull request #457 from npinchot:bug/date_not_constrained_to_startDate_and_endDate

Bug fix for date not being constrained between startDate and endDate