Treat Cookie object as session cookie if expiry = 0 is given.
With this change, you can specify session scoped cookies in an
external file setting expiry value to 0.
* src/Cookie.cc
* src/Cookie.h
* test/CookieParserTest.cc
* test/CookieStorageTest.cc
* test/CookieTest.cc
Added CookieStorage class which is based on RFC2109 and manages
cookies
more strictly than CookieBox and CookieBoxFactory class.
* src/CookieStorage.cc
* src/CookieStorage.h
* src/Cookie.cc
* src/Cookie.h
* test/CookieStorageTest.cc
* test/CookieTest.cc