greenio: socket.dup() made excess fcntl syscalls, added set_nonblocking=True kwarg to skip it; Thanks to Peter Portante
https://bitbucket.org/which_linden/eventlet/pull-request/27
setup: greenlet is actually required, remove --without-greenlet option, remove unused httplib2 test dependency; Thanks to Thomas Grainger
https://github.com/eventlet/eventlet/pull/12