SMS: Add rich content and IM style

It would be beneficial for clinics to have the ability to have conversations with patients through SMS rather than just accepting YES and NO for appointment reminders. 

For example, if the patient wanted to SMS the clinic about any questions, the clinic would be able to answer directly. 

Another example would be if the patient responds differently to an SMS appointment reminder. 

Other solutions also allow for rich content to be sent out, like being able to review the clinic through text.