NodeJS build

[ks2211]

Build only supports web browsers, need to use the wasm-pack bundler option to build for both node and browsers

[ks2211]

will need to support a different nats client library (nats.ws is used for browser, nats.js is used for nodejs). there is a shim to use the nats.ws library for node for the websocket but will require webpack compiling....looking for cleaner way