Merge "Pass environment variables of proxy to tox"

tox.ini

@@ -9,6 +9,7 @@ usedevelop = True
 install_command = pip install -U --force-reinstall {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
          PYTHONDONTWRITEBYTECODE = 1
+passenv = http_proxy HTTP_PROXY https_proxy HTTPS_PROXY no_proxy NO_PROXY
 deps = -r{toxinidir}/test-requirements.txt
 commands =
   find . -type f -name "*.pyc" -delete