Eventsource

* syntax clean up
* in listener:
* removed events buffering as a deque
* added toro dependency
* added toro.asyncresult to replace event's deque buffer
* used toro.asyncresult to block and call the event loop
* in client:
* added keep alive parameter

* moved event_loop callback rearming away
* changed events buffer from list to deque

* added invalid SSL certificates support
* integrated patches from Ian Whyman:
* support of bad HTTP services implementations (be compatible with '\n' and '\r\n')
* added user/password support for connections in client
* integrated patches from Коренберг Марк:
* use of json module of tornado
* cosmetic changes

* added support for SSL connections