Cookies class doesn't allow Header\Cookie instances

[vitorbrandao]

As opposed to the comment in Cookies:: addCookie:

Cookie should be passed either as a Zend\Http\Header\Cookie object or as a string

Cookies:: addCookie actually only allow instances of SetCookie to be passed as an argument.

The comment is not aligned with the implementation. Which one represents the expected behaviour?

[weierophinney]

Considering we test the code, the code is correct. Would you please create a PR to update the comment?

[vitorbrandao]

Yes, I will, Thanks @weierophinney.