neutron-lbaas py27 job fails on pyOpenSSL <= 0.13.1

[Ilya Shakhat]

According to requirements.txt allowed pyOpenSSL>=0.11. Currently the latest is 0.15.1 and tests are ok with this, however if version is enforced to 0.13.1 (as packaged in Ubuntu) tests fail:

neutron_lbaas.tests.unit.common.tls_utils.test_cert_parser.TestTLSParseUtils.test_read_private_key
--------------------------------------------------------------------------------------------------

Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):
      File "neutron_lbaas/tests/unit/common/tls_utils/test_cert_parser.py", line 238, in test_read_private_key
        ENCRYPTED_PKCS8_CRT_KEY)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 422, in assertRaises
        self.assertThat(our_callable, matcher)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 433, in assertThat
        mismatch_error = self._matchHelper(matchee, matcher, message, verbose)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 483, in _matchHelper
        mismatch = matcher.match(matchee)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/matchers/_exception.py", line 108, in match
        mismatch = self.exception_matcher.match(exc_info)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/matchers/_higherorder.py", line 62, in match
        mismatch = matcher.match(matchee)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 414, in match
        reraise(*matchee)
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/matchers/_exception.py", line 101, in match
        result = matchee()
      File "/home/ishakhat/Work/neutron-lbaas/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 969, in __call__
        return self._callable_object(*self._args, **self._kwargs)
      File "neutron_lbaas/common/tls_utils/cert_parser.py", line 64, in _read_privatekey
        return crypto.load_privatekey(crypto.FILETYPE_PEM, privatekey_pem, cb)
    OpenSSL.crypto.Error: [('PEM routines', 'PEM_READ_BIO_PRIVATEKEY', 'bad password read')]

[Ilya Shakhat (shakhat)]

Resolved by bumping pyOpenSSL to >=0.14. Commit: https://review.openstack.org/#q,I5590b3244decf3e289a027ebe388b528ea403e0d,n,z