Fetures: checkboxes transformed to toggle switches, clockpicker for time input
readonly input fields : input time with clockpicker only (to avoid input typing and format mistakes), better visualisation for year and weeks selection (in addsgift.php)
added 'clockpicker' library (could replace jquerry-ui timepicker later on in some files)
modified functions.display.php to handle external classes
modified addrow-v2.js to display cloned values and init clockpicker
