Import eventlet in __init__.py

All of this is because if dnspython is present in your environment then
eventlet monkeypatches socket.getaddrinfo() with an implementation
which doesn't work for IPv6. To turn this off you need to set an
environment variable before you do the import.

Resolves bug 1164822.

Change-Id: I2382db7b3ac4a2d940e0c45dfe3d48f499de2f16
Merge "Import eventlet in __init__.py"