lib: only maintain one copy of safe_str / safe_unicode The standalone-ish nature of vcs gets a bit in the way. It already depends on some very generic Kallithea functionality. But for now, avoid code duplication, and let Kallithea use vcs functionality instead of duplicating it.

[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}