new arrival tag improvements

As a marketing user I want the system handle product "newarrival" tag automatically.
I would like to specify number of days before now() that count as new on SHOP and CATEGORY level.
I also would like the system to included products that have "newarrival" tag set explicitly and put them to top of results

Tech:
1. Add SHOP setting for newarrival tag days
2. Add CATEGORY setting for newarrival tag days
3. Modify TagSearchQueryBuilder to account for this logic