[skeleton] fix new class configuration in realdbtest

[web request] fix cookie 'expires' formating (closes #1953945) This was because cookie.expires wasn't processed in cw.etwist.http, though this code should had never existed, instead proper twisted method should be called. Also, move on the way to headers handling simplification and rewrite cw request.set_cookie / remove_cookie to directly use the Cookie class in cw.web.http_headers rather than going back and forth simple cookie <-> raw string <-> http_headers.Cookie IMO more on this should be done.

[web] properly redirect when user login on loggedout view (closes #1954050) This avoid getting a "you've no access to this view" message

[i18n] update