HV-905 Providing a global config for auto unwrapping

An early attempt. Any thoughts on the direction?
> This does not seem right to me, as "integerProperty" is just a "wrapped" property. Also @Min(value = 3) IntegerProperty integerProperty does not require the @Valid. 

Agreed. I think there is a misunderstanding.

Lets look at some cases here:

    @Min(value = 3)
    IntegerProperty integerProperty 

Out of the box this is just normal Bean Validation. A `ConstraintValidator` implementation for `IntegerProperty` must be registered otherwise an exception is thrown. Alternatively the global automatic unwrapping flag is set and we iterate the registered un-wrappers and find the JavaFX one.

Next:
 
    @UnwrapValidatedValue
    @Min(value = 3)
    IntegerProperty integerProperty 

Not much to say. Explicit unwrapping.

Now it gets interesting:

    Property<@MinTypeUse(value = 3) Number> integerProperty = new SimpleIntegerProperty( 2 );

* With the global un-wrapping option set, there is no question. Unwrapping should be applied.
* W/o the global option we get into the case where @gunnarmorling and I seem to disagree atm. The way I see it, is 
that we have a property validation of `integerProperty`. Since there is no `@Valid` we don't have cascaded validation. Adding `@UnwrapValidatedValue` would make the case clear and I think that is what @gunnarmorling wants to enforce. My pov is that just placing the constraint onto Number makes it sufficiently clear that unwrapping is needed. For this reason I think we should not enforce the use of `@UnwrapValidatedValue`. For me it is implicit. 

Last but not least:

    @Valid
    private Property<@MinTypeUse(value = 3) Number> integerProperty;

Here we have cascaded validation, meaning we validate the internas of `Property`. Here comes also the approach in @gunnarmorling wanted to implement initially. Basically `MinTypeUse` would be applied on the internal state of `Property`. This would amongst other things require that there is a field or a getter for this generic type in the  implementation. How the property would be accessed was one of the things we kept discussing. Anyways, we don't support this for now.

@gunnarmorling, do you agree with this assessment?