Add Calendar using QCalendarWidget

[private-yusuke]

This PR adds Calendar, a component inheriting QCalendarWidget.

Example

import{DateFormat,DayOfWeek,NativeElement,QCalendarWidgetSignals,QDate,}from"@nodegui/nodegui";import{Calendar,Renderer,useEventHandler,Window,}from"@nodegui/react-nodegui";importReactfrom"react";constApp=()=>{constcalendarClickHandler=useEventHandler<QCalendarWidgetSignals>({activated: (nativeDate)=>{constdate=newQDate(nativeDateasunknownasNativeElement);console.log(`activated: ${date.toString(DateFormat.SystemLocaleDate)}`);},clicked: (nativeDate)=>{constdate=newQDate(nativeDateasunknownasNativeElement);console.log(`clicked: ${date.toString(DateFormat.SystemLocaleDate)}`);},currentPageChanged: (year,month)=>{console.log(`currentPageChanged: year, month: ${year}, ${month}`);},selectionChanged: ()=>{console.log("selectionChanged");},},[]);return(<Window><CalendarfirstDayOfWeek={DayOfWeek.Sunday}on={calendarClickHandler}/></Window>);};Renderer.render(<App/>);