* Enable prefer-const rule
Stylistically I don't like this but Closure Compiler takes advantage of
this information.
* Auto-fix lints
* Manually fix the remaining callsites
* Update transforms to handle ES modules
* Update Jest to handle ES modules
* Convert react package to ES modules
* Convert react-art package to ES Modules
* Convert react-call-return package to ES Modules
* Convert react-test-renderer package to ES Modules
* Convert react-cs-renderer package to ES Modules
* Convert react-rt-renderer package to ES Modules
* Convert react-noop-renderer package to ES Modules
* Convert react-dom/server to ES modules
* Convert react-dom/{client,events,test-utils} to ES modules
* Convert react-dom/shared to ES modules
* Convert react-native-renderer to ES modules
* Convert react-reconciler to ES modules
* Convert events to ES modules
* Convert shared to ES modules
* Remove CommonJS support from transforms
* Move ReactDOMFB entry point code into react-dom/src
This is clearer because we can use ES imports in it.
* Fix Rollup shim configuration to work with ESM
* Fix incorrect comment
* Exclude external imports without side effects
* Fix ReactDOM FB build
* Remove TODOs I don’t intend to fix yet
* shared/src -> shared
It's not a real package and doesn't even have package.json.
This will also make importing less weird if we drop Haste.
* Get rid of shared/utils
Moved event-specific into shared/event.
Moved rest to the root since distinction has always been pretty arbitrary.
* Fix references to old shared/src paths
