B13767 this fix prevents marking elements with class .btn to required color,...

B13767 this fix prevents marking elements with class .btn to required color, which aren't given from forms itself (all form buttons are 'button' tags). In this case we need to filter out anchor tags with blank href (#) (sometimes used as buttons from other js frameworks like datetimepicker to trigger some functions). Also implemented new CSS lines to overwrite specific bootstrap.css rules for the datetimepicker (arrows are higher positioned, which looks better than before)