HV-905 Providing a global config for auto unwrapping

An early attempt. Any thoughts on the direction?
> 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. 

No, I don't want to enforce `@UnwrapValidatedValue`. I'd auto-unwrap it if this has been enabled through the global flag. Plus, I'd do it in the same way `@Min(value = 3) IntegerProperty integerProperty`. Both cases fall into the same category to me.

> I would expect this to work, since it is what I called in the previous comment "implicit unwrapping".

Yes, same here. Only that I think "implicit unwrapping" should be enabled on a global level. Alternatively, we also can do it by default (but then also for "normal" constraints on wrapper-typed properties) if there an unwrapper exists and there is no validator for the constraint and the wrapper type itself. If an unwrapper exists and a constraint for the wrapper type exists, unwrapping would have to be explicitly requested for that property through `@UnwrapValidatedValue`.