Consider Supporting vegafusion

[jeremiahpslewis]

Cross post from vega/vegafusion#81

As a minimal proof of concept, vegafusion-server binaries are now available for many platform via Yggdrasil (Julia's binary building infrastructure) and the Julia package registry. Julia already has an Altair equivalent, VegaLite.jl which could be updated to support a vegafusion-server backend.

Motivation: Julia plotting libraries which can support massive datasets and high processing demands tend to be more successful Makie.jl, VegaLite.jl has been held back by lesser performance on large-n use cases. Likewise Julia is home to a community of high performance computing projects (and enthusiasts) who would particularly appreciate the boost a project like vegafusion has to offer.