[RFC] Versions in docs?

[adamelso]

I was initially going to propose docs for each version of Sylius, like Symfony and Doctrine have.

Instead while Sylius is still in development, adding version note blocks before certain descriptions maybe more clearer.

Examples:

These docs have been written for Version 0.13.

and

In versions before 0.10, The Sylius\Component\Cart\Model\CartItem was previously namespaced as Sylius\Bundle\CartBundle\Model\CartItem.

The benefit of this would be that the breaking changes between development versions would be noted.
Fortunately it's through my understand of the codebase that I've been able to make fixes myself where the docs are out of date.

The disadvantage of this would be that this may cause more confusion rather than less.