[WIP] feat: use http-cookie for better Cookies spec compliance

Instead of WebAgent 0.6.2 that is not maintained over 10 years. To omit
maintaining that library use http-cookie for better spec compliance and
healthy development.

This introduces following incompatibility from existing cookies
implementation.
* Expired cookies are not saved. With the old implementation expired
  cookies are saved in file and not be sent to the server. With the new
  implementation the expired cookies are not saved to the file and not
  be sent to the server.
* Cookie#url -> Cookie#origin
* Cookie#domain returns dot-less domain for domain cookies. Instead,
  Cookie#dot_domain returns with dot.