fix(datepicker): invalidate manual input value with non-existant day

Datepicker was accepting manually input values with non-existant days, like '31/02/2014', because the javascript Date object would overflow the day value and give back '03-03-2014'. This fix checks the parsed day to see if it matches the input day value, otherwise, it invalidates the input.

Fix for #816
feat(modal): Prevent wheel event on modal backdrop
fix(tooltip): add backdropAnimation to parsed attributes (closes #1327, fixes #1326)