Draggable: [feature-request] Snap grid

[matthew-dean]

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2. Describe the bug or feature

Some drag/drop libraries allow the definition of a "snap grid", such that items that are dropped (or dragged) will align to the grid. Snapping is often configurable by which side of the element should align with the grid (or all sides). (See the "Snapping" section here: https://interactjs.io/.) I know this library has a "snapping" feature, but it doesn't seem configurable to a repeatable "grid" within an element, which is the feature I'm interested in.

[zjffun]

This is a very useful feature. I will start trying to implement a plugin to support it this weekend.