0.6.0

• Add secure constructor option for secure connection checking
• Change constructor to signature new Cookies(req, res, [options])
  • Replace new Cookies(req, res, key) with new Cookies(req, res, {'keys': keys})
• Change prototype construction for proper "constructor" property
• Deprecate secureProxy option in .set; use secure option instead
  • If secure: true throws even over SSL, use the secure constructor option