Add RichMessaging constructors to TIA

[benjaminloerincz]

Add these constructors of namespace RichMessaging to TIA:

• RichMessaging.AuthRequestResponse(String accessToken, String contextRecordId, String authProviderName)
• RichMessaging.AuthRequestResult(System.PageReference redirectPageReference, RichMessaging.AuthRequestResultStatus resultStatus, Datetime expirationDateTime)
• RichMessaging.PaymentLineItem(String label, Double amount)
• RichMessaging.PaymentLineItem()
• RichMessaging.TimeSlotOption()
• RichMessaging.TimeSlotOption(Datetime startTime, Integer duration)
• RichMessaging.TimeSlotOption(Datetime startTime, Datetime endTime)