pool: fix Issue 36: TypeError raised from pool.join(raise_error=True). Original patch by David Hain.

test__pool.py: add test for Issue 36: TypeError raised from pool.join(raise_error=True). Original patch by David Hain.

--HG--
rename : greentest/test__server_close.py => greentest/xtest__server_close.py

test_ssl.py: copy all new tests and updates from Python 2.7 (but make it pass on older versions too)

fix test__socket.py to expect SSLSocket to raise SSLError in case of timeout rather than socket.timeout