Simplify "kEvent" class constructor

Method Signature Changed: kApplication::HandleEvent (removed optional "$params" and "$specific_params" parameters) kEvent::__construct (replaced required "$params" parameter with required "$event_string" parameter) kEvent::copyFrom (the "kEvent" type hint added to "$source_event" parameter) kEvent::setRedirectParams (the "array" type hint added to "$params" parameter) Solution in "kApplication::HandleEvent" method: add "$params" and "$specific_params" parameters back, but add "array" type hint to them when "$params" parameter is an array, then use "kUtil::deprecateParameter" method to trigger notice about usage of $params/$specific_params parameters use "kEvent::fromArray" method to create event, that will replace "$event" parameter value extract logic, that transforms "$params" array into string from public static "kEvent::fromArray" into protected static "kEvent::arrayToString" method in "kEvent::__construct" method, when "$event_string" argument turns out to be an array: use "kUtil::deprecateParameter" method to trigger notice about usage of $params parameter use "kEvent::arrayToString" to transform "$event_string" parameter value