JavaScript support + example

[theRealWardo]

wouldn't it be nice if you could write high performance Envoy extensions in the #1 most used language in the world?

This requires a good bit of technical work, but it should be doable if we build on wasmedge-quickjs

[theRealWardo]

Second State wrote a good article on this - https://www.secondstate.io/articles/run-javascript-in-webassembly-with-wasmedge/