A spike for testing out using react-dnd with hx.

Currently implements the chess example from the dnd documentation site (without movement limitation).

Builds with shadow-cljs, so makes all of the environment assumptions that it does.

Run with npx shadow-cljs watch app, then open a Chrome browser at http://localhost:3000

Uses html5 dnd, so is not guaranteed to work in other browser than Chrome.

Enjoy!