Add support for synchronous layout #8
Description
The @hpcc-js/wasm graphviz.layout function is asynchronous and returns a promise. In some situations it would be beneficial to be able to do the layout synchronously and obtain the layout directly.
This is an enhancement proposal to implement such a function that returns the layout directly.
Here are two cases where the now archived Viz.js v1.x is used synchronously:
Since d3-graphviz is currently in the process of being ported from Viz.js to @hpcc-js/wasm it would simply things a lot if @hpcc-js/wasm also had a function for performing the layout synchronously.