dev_requirements.txt: bump minimum pytest versions to a working set Not all combinations of pytest-related packages seem to work. Trial-and-error lead to these combinations of minimum versions. Add a minimum bound to pytest-benchmark and pytest-localserver to help pip in figuring out a suitable combination with pytest, and also to allow testing minimum combinations in the future. Drop pytest-runner, which should not be needed unless when running tests directly from setup.py.

[tox]
minversion = 1.8
envlist = py27-pytest

[testenv]
setenv =
    PYTHONHASHSEED = 0
deps =
    -r{toxinidir}/dev_requirements.txt
    python-ldap
    python-pam
commands =
    pytest: py.test {posargs}