function _initCalendar(){
           if(typeof yobi.ui.Calendar === "function"){
               $('[data-toggle="calendar"]').each(function(i, el){
                   yobi.ui.Calendar(el, {
                       "silent": true
                   });
               });
           }
        }
Initialize ui.Calendar
This function called after redraw issue list HTML using PJAX.

@private