Chainable Set

[curran]

It would be useful if set returned the instance, so that you can chain set calls.

For example, setting up the Topologica instance on a D3 local and setting the selection.

Before:

const state = Topologica({ circlesDOM });
state.set({ selection });
return state;

After:

return Topologica({ circlesDOM }).set({ selection });

Full example: https://vizhub.com/curran/27c261085d8a48618c69f7983672903b