Add support of 'select' from option list in ConsoleIO and NullIO

Sometimes it is useful in scripts (script handlers, plugins) to have ability to choose values from list of predefined options during console interactions. This pull request makes it possible due to support of 'select' method in IOInterface
@stof I know about DialogHelper. So do you think that bumping to ~2.5 is harmful for us?
I kept in mind that it would be nice in future to refactor console functionality in order to use more handy 2.5 Question system (just like you've mentioned in comment above), therefor i've chosen the way and not the old one.
Moreover there is another advantage of Question system - ChoiceQuestion makes it possible to have a list of **values** from $choices list itself as an *ask* result. In opposite DialogHelper's *select* returns only **keys** from $choices array