Implements HTTP cookies, as described by RFC 6265.
To have a [class@Session] handle cookies for your appliction automatically, use a [class@CookieJar].
name and value will be set for all cookies. If the cookie is generated from a string that appears to have no
name, then name will be the empty string.
domain and path give the host or domain, and path within that host/domain, to restrict this cookie to. If
domain starts with ".", that indicates a domain (which matches the string after the ".", or any hostname that has
domain as a suffix). Otherwise, it is a hostname and must match exactly.
expires will be non-null if the cookie uses either the original "expires" attribute, or
the newer "max-age" attribute. If expires is null, it indicates that neither "expires" nor
"max-age" was specified, and the cookie expires at the end of the session.
If http_only is set, the cookie should not be exposed to untrusted code (eg, javascript), so as to minimize the danger posed
by cross-site scripting attacks.