Also update the SSL test for Python 2.7 to test the fix for Python bug
 no. 23804. This may need some tweaking for the 2.7.8 environment to
disable some tests. We'll let Travis run 2.7.8 to find out.

Move 3rd party libraries to deps/ directory.

Move gevent and greentest to src/ directory. This fixes tox.

At this point the builds should all work the same. Lets check.

On travis, start a build with 2.7.8 so that _ssl2.py gets
tested (previously tested by Python 2.6). Do so with the test_ssl.py
from that version (because the changes are large), but keep using the
2.7.11 tests with just a few removals otherwise.

On travis, start a build with 2.7.8 so that _ssl2.py gets
tested (previously tested by Python 2.6). Do so with the test_ssl.py
from that version (because the changes are large), but keep using the
2.7.11 tests with just a few removals otherwise.

Also update the test_ssl.py to cpython rev 2c9ff9e (head). This fixes the
problems with invalid certs for svn.python.org.

These tests include much more testing of the new-in-2.7.9 SSLContext
settings, which revealed some problems in our hostname validation, our
handling of read/write/do_handshake for closed sockets, and the missing
alpn_selected method.

The cert for svn.python.org has changed breaking many test_ssl.py cases.

The upstream resolution is being discussed in
https://bugs.python.org/issue25940, but the interim solution was to
disable the failing tests to avoid blocking releases. I'm applying the
same approach here for a temporary fix.

AppVeyor: Make a number of timing-related tests less strict, hopefully fixing most of the appveyor failures

issues_671: Make more robust by sending a second signal and printing diagnostics.
Skip the few test cases that are still timing out unreliably on appveyor.
More explicit tests for gevent.Timeout functionality plus timing fixes.

Fix the last test_ssl failure (test_protocol_sslv2) for CPython 2.7.8 and .9. In python Issue 20207, the SSLv2 protocol was disabled by default, and thus the test was changed to expect a failure (see https://github.com/python/cpython/commit/65f2fdce200b800bd95ac6690e9654afc37897c6).  Match that change.

Tested under Python 2.7.8 and all the test_ssl tests pass, EXCEPT for:
-- test_algorithms. That test is disabled in the 2.7.8 sourcecode, so disable it here;
-- test_protocol_sslv2, which fails with the same EOF error as described in the last commit for 2.7.9.

Fixes several test failures under 2.7.9, notably test__pywsgi and test__ssl.
There are lots of whitespace differences in the tests due to forking for CPython
<= 2.7.8.

The complete failure list follows.

The ONLY failure in 2.7/test_ssl has this traceback; I'm not sure what the cause is yet:

  ======================================================================
  ERROR: test_protocol_sslv2 (__main__.ThreadedTests)
  ----------------------------------------------------------------------
  Traceback (most recent call last):
    File "test_ssl.py", line 71, in f
      return func(*args, **kwargs)
    File "test_ssl.py", line 1205, in test_protocol_sslv2
      try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_SSLv23, True)
    File "test_ssl.py", line 979, in try_protocol_combo
      chatty=False, connectionchatty=False)
    File "test_ssl.py", line 909, in server_params_test
      s.connect((HOST, server.port))
    File "/gevent/gevent/_sslgte279.py", line 546, in connect
      self._real_connect(addr, False)
    File "/gevent/gevent/_sslgte279.py", line 537, in _real_connect
      self.do_handshake()
    File "/gevent/gevent/_sslgte279.py", line 504, in do_handshake
      return self._sslobj.do_handshake()
  SSLEOFError: EOF occurred in violation of protocol (_ssl.c:581)

  ----------------------------------------------------------------------

3/123 expected failures
 - //bin/python -u -m monkey_test test_ssl.py
 - //bin/python -u test__socket_dns6.py
 - //bin/python -u -m monkey_test --Event test_ssl.py

4/123 unexpected failures
 - //bin/python -u test__all__.py
 - //bin/python -u test_ares_timeout.py
 - //bin/python -u -m monkey_test test_httpservers.py
 - //bin/python -u -m monkey_test --Event test_httpservers.py

it no longer depends on specific minor python version

that way test runner does not fail on ubuntu where this tests are not available
a new test__monkey_patching.py is added which runs all stdlib tests

- version-neutral syntax for print and exec
- version-neutral exception handling: use exc_info()
- version-neutral exception raising: use raise A("x"), not A, "x"
- use e.args[0] instead of e[0]
- use urllib.request if urllib2 unavailable
- use http.client if httplib not available
- use socketserver if SocketServer not available
- use test.support if test_support not available

test_ssl.py: use urllib.request/parse instead of urllib2/urlparse; use http.server instead of HTTPServer

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