* Completed mostly working version

 * Completed mostly working version
   * Moved to a mode where addevent calls a callback rather than
     it being instantiated within.
     * If the callback returns -1, then no event is ever setup
     * Otherwise the integer value is used to setup the event
     * This allows for using coroutine.wrap rather than a cooked-up wrapper
  * Tests work, although there are a few remaining issues:
    * Need to figure a good way of preserving the event object,
      not sure if current method is good enough, since the socket
      is the only anchor, and it is only held inside the coro..
      circular reference, something that Lua 'handles' well.
    * Doing more than the maximum sockets the process is allows
      causes strangeness to occur in libevent.. somehow
      it is getting around to epoll_add which is causing valgrind
      to barf.