[ZF3] Clean Stdlib

* Remove fluent interface for options class
* Remove the Hydrator classes from Stdlib as it will have its own component (https://github.com/zendframework/zf2/pull/5000)
* Remove deprecated classes
* Updated tests
* Remove InitializableInterface because this interface was introduced for doing bad things (the infamous init method).
* CallbackHandler class is a bigger refactoring (see [this PR](https://github.com/zendframework/zf2/pull/5229)).

Some notes while checking the code:

* I don't remember the status about ArrayObject. I thought we wanted to throw it out no?

Don't hesitate to quickly check this namespace. It's pretty quick and most classes are small.


PS: This optimization for case-insensitive method names has already be merged. There is no issue with the magic method `__call` because this method check availability using `method_exists` - so `__call` is never be called.