Adding drag drop functionality instead of click on control sidebar

[abhimanusharma]

Hi,

Designing the form using this form builder is very efficient, its just that in smaller screen and responsive scenario add section button hides in the bottom. Also listing control in sidebar taking so much space, we can replace them with icon to make it look more compact.

Here is an example of better UI aspect of future of vue-form-builder https://github.com/unlayer/vue-email-editor
Adopting futuristic design approach can reduce app size and make the more compact design when we use the vue-form-builder in Modal/popups.