Fix windows issues

[hbruch]

This PR fixes some failures when running the tests under windows:

When running the tests under windows:

>py.test -v -s
============= test session starts =============================
platform win32 -- Python 3.5.1, pytest-3.3.1, py-1.5.2, pluggy-0.6.0 -- c:\...\python.exe
cachedir: .cache
rootdir: C:\geocoder-tester, inifile: pytest.ini
collected 12752 items / 1 errors

!!!!!!!!!!!!!!!!!!! Interrupted: 1 errors during collection !!!!!!!!!!!!!!!!!!!
========= 12752 tests deselected ============================
========= 12752 deselected, 1 error in 4.89 seconds ================

[yohanboniface]

Thanks!