`loadFromString`, `loadFromDataURI` so known when ready and set
- Docs (Refactoring): Formally specify `Promise` resolve type;
add `typedef` for dialog result object; add an
`ArbitraryCallbackResult` type
- Refactoring: Use array destructuring for clearer var naming;
prefer `includes` over `indexOf`
- Docs (CHANGES): Update
- Build: Update dist files for non-ES use