[WIP] Enable Repeatable Attachments

[felipeelia]

Closes #12

• [ ] Test if it works for email fields as well (To and From)
• [x] Test if it works for multiple fields
• [x] Test if it works for multiple groups
• [ ] Test if it works for multiple groups with multiple fields
• [ ] Test if it doesn't break anything else

[mahdi-ln]

Doesn't work 😢

[dr5hn]

This works!

if your group name is [emails]

[emails]
GROUP #[group_index]
	Checkbox: [your-checkbox]
	E-mail: [your-email]
	Radio: [your-radio]
	Select: [your-menu]
    Files: [dog-image]
[/emails]

and your file name is [dog-image]

Then in the attachments field, you have to write [emails_dog-image]