Feature Request: Field Validation

[camya]

Hi, first of all thank you for this great project. It's really useful already in this early stage.

I think it would be useful to implement some kind of field validation.

It should be possible to add no validation at all or as many as you want. The validation list should be sortable. Validations are processed from top to button.

• Title: Just a title / description of the validation
• Type: Select [Regex | Email | URL | Character Max | Character Min | API request | ... ]
• ?: Input for selected type. Could be an Text field for Regex, or an Input type="number" field for Character Min/Max, or options like "Disallow external links" for URL validation.
• Error message: The error message as shown to the user.

[RobStino]

@greenphp This is a great idea. One we've briefly talked about, but you capture it really well!