Add documentation for all props

[akshitkrnagpal]

Not all props are documented in the Readme.

react-sign-in-apple/src/index.tsx

Lines 4 to 28 in 82ed258

	interface Props {
	clientId: string
	redirectURI: string
	scope?: string
	state?: string
	responseType?: string | 'code' | 'id_token'
	responseMode?: string | 'query' | 'fragment' | 'form_post'
	nonce?: string
	usePopup?: boolean
	onSuccess?: Function
	onFailure?: Function
	mode?: string
	type?: string
	appearance?: {
	color?: 'black' | 'white'
	border?: boolean
	borderRadius?: number
	width?: number
	height?: number
	}
	render?: (props: {
	onClick: (e?: any) => void
	disabled?: boolean
	}) => JSX.Element
	}