Support a React/next.js-like framework

Hey folks! Now that I've managed to get the installation process under control, I'm starting to focus on getting a really minimal, but productive frontend framework working that either uses or is based on React/Preact & next.js/Vue.

This has been more difficult than I thought because some of React's paradigms don't really translate 1:1 to Go. Specifically how they do setState and some of the lifecycle methods like componentWillReceiveProps are tough to model in the same way.

I'll be filling in this issue with more information and thoughts as I go, but I'm also looking for ideas. We have tons of variables we can tweak, so it's just about figuring out what feels right. For example, some of the options we have are: tweaking React's API a bit to more like idiomatic Go, generating additional Go code via go generate, updating Joy's JS output to better support React.

Please help make Go great for web development!