Fix datepicker broken by update to Angular 1.3

*  Update Angular Bootstrap
*  Fix to start week in datepicker popup at Sunday and not Monday
*  Send string for date display, and save as Date object (Date object in display also shows time part and time zone)
*  Fix validation being called with undefined date

There are a number of open issues around the datepicker in Angular 1.3 against angular-ui, but this seems to get things working again for our use of it.