socket: change order of arguments to ssl_listener to be in line with wrap_ssl() function; fix the tests

- all the functions from __init__.py were moved to gevent/greenlet.py; __init__ imports only some of them back
- gevent.timeout is now known as gevent.Timeout
- Hub now tries to recover after dispatch() failures (seen only(?) on epoll even though event_reinit() was called as necessary)
  This helps to pass test_socketserver.py all the time, not occasionally like before
- wsgi_test.py: move ssl tests to a separate class
- libevent version checking is gone as its done by gevent.core now

--HG--
rename : gevent/__init__.py => gevent/greenlet.py

gevent.core: loop() and dispatch() now raise IOError if corresponding libevent functions return an error

core.pyx: make it compatible with libevent-1.3 which does not have _EVENT_VERSION nor event_reinit()

Thanks to Litao Wei for finding this out.

add test_queue.py from standard tests to check how good is gevent.queue.Queue a replacement for standard Queue

no good at all, fails miserably

gevent.socket.GreenSocket: use socket from standard _socket for wrapped instance instead of standard socket.py

this only affects Python 2.6, which fixes the imports in modules run by runpy.py