Exclude Offers in decisioning phase through Ranking formula

Currently even Offers with a Ranking score of 0 will be sent back as a response. It should be possible to avoid sending back Offers to the customer based on the value of the Ranking formula (e.g. if the value is 0).

Some conditions need to be generally applied without having the risk that someone forgets to apply them. Therefore these conditions are not put into the Offer eligibilities (recurring risk to forget them) but they are put in the ranking formulas so that they are automatically generally applied.