Represents preferred values along a single content negotiation dimension.
The number represents how preferred this value is from 0 to 1. Follows the quality values rule from RFC 7231: "The weight is normalized to a real number in the range 0 through 1, where 0.001 is the least preferred and 1 is the most preferred; a value of 0 means "not acceptable"."
A single entry of a ValuePreferences object. Useful when doing operations on such an object.