Submit a form asynchronously in Ajax mode

Description

To make Episerver Forms use $.ajax() to submit a form asynchronously, do one of the following:

• set JavaScript object epi.EPiServer.Forms.AsyncSubmit to true
• decorate the <form> tag with attribute *data-epiforms-async-submit="true" *

Otherwise, a form submits SubmissionData to serverside synchronously (to prevent a visitor from continuously clicking Submit).