Browser: Initial cookie storage implementation

This adds storage for cookies that maye be set via 'document.cookie' in
JavaScript or the Set-Cookie HTTP header. For now, it parses only the
name-value pair from a set-cookie line, but does not parse optional
attributes.

Currently, storage is ephemeral and only survives for the lifetime of
the Browser instance.

Userland/Applications/Browser/CMakeLists.txt

@@ -6,6 +6,7 @@ set(SOURCES
     BookmarksBarWidget.cpp
     BrowserConsoleClient.cpp
     ConsoleWidget.cpp
+    CookieJar.cpp
     DownloadWidget.cpp
     History.cpp
     InspectorWidget.cpp