Make Order number unique in db

[asvishnyakov]

While we require and generate unique order numbers, there are no restrictions in db for it

[5309]

We generate unique Order numbers by default, but we should not restrict Order number to be unique. For example, the same Virto Commerce installation might be used by a few legal entities with the same kind of Order number sequences. In this case, there might be few orders with the same Order number.

The problem is that API method /api/order/customerOrders/number/{number} is designed to return only one Order by number.

@tatarincev how it can be resolved?

[asvishnyakov]

Not only this one, but in storefront too

[tatarincev]

I think that this method /api/order/customerOrders/number/{number} should be marked as Obsoleted with future remove