v4.0.0 2021-08-16

• [BREAKING-CHANGE] remove module Same_site. Use same_site type instead.
• [New] introduce type same_site to replace Same_site module and to better conform to RFC 6265.
• [New] add of_cookie features an angstrom parser to parse 'Cookie' header value as specified by RFC 6265.
• [New] add pp, pp_date_time and pp_same_site pretty prints type t, date_time and same_site respectively. Useful for debugging pruposes.
• [New] add date_time function to create valid date_time value.
• [BREAKING-CHANGE] make date_time type abstract
• [BREAKING-CHANGE] to_set_cookie_header_value has been removed. Use to_set_cookie instead.
• [BREAKING-CHANGE] to_cookie_header_value has been removed. Use to_cookie instead.
• [BREAKING-CHANGE] of_cookie_header has been removed, Useof_cookie instead.
• [BREAKING-CHANGE] remove Cookie exception. The library is now exception less, i.e. uses result type to denote error scenarios.
• [New] add of_set_cookie to parse HTTP Set-Cookie header
• Add expect tests