[Forms] Set-up an auto-response for e-mail fields

**Is your feature request related to a problem? Please describe.**

If a user has to submit their e-mail address in a form, they might often need to receive an e-mail with additional information.
Often, they would expect to receive a confirmation e-mail.

**Describe the solution you'd like**

Add the following properties to the e-mail form field:
- an `Is Auto-replying Enabled` switch
- an `Auto-reply message` text property where the admin can add their custom message
- even better if the field allows for formatted text to be e-mailed