Run tests against Python 2.6, 2.7, 3.3, 3.4 and PyPy2

In particular it includes:
- some extension of CONTRIBUTING.md
- one fix for Python 2.6 in tests/integration/cli_test.py
- one fix for Python 3.3 in tests/integration/service_test.py
- removal of unused imports

Make stream_output Python 3-compatible

Signed-off-by: Frank Sachsenheim <funkyfuture@riseup.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/setup.py b/setup.py
index b7fd4403..cdb5686c 100644
--- a/setup.py
+++ b/setup.py
@@ -48,7 +48,7 @@ tests_require = [
 ]
 
 
-if sys.version_info < (2, 6):
+if sys.version_info < (2, 7):
     tests_require.append('unittest2')
 if sys.version_info[:1] < (3,):
     tests_require.append('pyinstaller')