[SysApps] Add Raw Sockets stub

Just the skeleton to serve as base for the interfaces implementation. No API is
currently exposed.
delta
[SysApps] Add the RawSocketObject

This class is going to concentrate all the shared code among
the different interfaces of the Raw Socket API. Currently only
the ReadyState is shared.
[SysApps] Make it possible to create a TCPSocket from a connected socket

The TCPServerSocket will need to create a TCPSocket from incoming connections.
This patch makes it possible to create an object in the native side first and
handle the identifier to the JavaScript context.
delta
[Sysapps] Add browser tests for the Raw Socket JavaScript API

Tests if the objects are leaky and if the basic functionality like
send and receive data works. These tests are not API conformance tests.