Support columns grid

[patrickphat]

Is your feature request related to a problem? Please describe.
I really love this project and I would like to request column drag-and-drop feature. So that we can leverage grid layout for more flexible editing

Describe the solution you'd like
Drag and drop a component to the side of another components to create columns

Describe alternatives you've considered

Additional context
Add any other context or screenshots about the feature request here.