Sync latest setup.py from oslo.

This commit syncs the lastest version of setup.py from oslo,
which includes:

8842a00 openstack.common.setup: fails to get version from git
8ce5947 Change the check for the existence of .git directory.
7417a60 returncode for Popen is valid only after communicate call

Change-Id: I491381b2f9cb178bb1d9aa9e790cc7fd11a67d2f
1 file changed