Pagination utility adjustments

• PaginationParameter moved to Ardeidae\Flight\Pagination namespace.
• PaginatableProperties trait added to Ardeidae\App namespace; when used in an object, it provides a method that constructs a PaginationParameter from the object's Limit/Page properties (that should be typed appropriately) - intended for use in situations such as receiving a request that contains scalar values that will be used to paginate a query.