feat(ScriptAPI): timeout & interval

[MukjepScarlet]

Note: body of callback will be always executed on the main thread (render thread).
example:

const id = setTimeout(() => {
    Client.displayChatMessage("1111");
}, 5000);

clearTimeout(id);

Note: the Kotlin auto-generated FunctionN interfaces don't have @FunctionalInterface annotation, so it can't be cast by Polyglot.