[PoC] Pricing configuration

Add validate pricing calculator configuration. This to prevent failure when we change calculator type.
@pjedrzejewski  I'll squash commits if you are agree.

Note: Forgot create new branch, There are two files not associated with this PR.
  - src/Sylius/Bundle/ResourceBundle/Controller/Configuration.php
  - src/Sylius/Bundle/ResourceBundle/Controller/RedirectHandler.php
Please add new line before this.