fix bug:when selected-date and pre-selected-date is in the same view, the pre-selected-date's text color is still black
fix bug:when selected-date and pre-selected-date is in the same view, the pre-selected-date's text color is still black

jeremiescheer/THCalendarDatePicker,AliCormackDistance/THCalendarDatePicker,AliCormackDistance/THCalendarDatePicker,powfulhong/THCalendarDatePicker,tranhieutt/THCalendarDatePicker,jeremiescheer/THCalendarDatePicker,powfulhong/THCalendarDatePicker,tranhieutt/THCalendarDatePicker