Form builder widget

[d4rekanguok]

I'm needing this right now. A client want to be able to edit their form setups, which they have a few of. Would be neat to build a widget that spit out a form structure.

It only needs to be very basic:

• Support a default set of input: string, text, boolean, select, upload, number
• Each input needs required / readonly
• Input hint
• Input size: 1, 1/2, 1/3, 1/4

Advanced:

• input group
• logic (show additional input based on value of another input)
• i18n
• user can register custom input types

For very simple form we can actually just use netlify-cms's list widget, but it's fairly clumsy UI-wise (difficult to add, every fields looks huge).