Added proxy settings to tox.ini
Added proxy settings to tox.ini

Change-Id: Ib5369b3235fb6c5fd4b5e9c950c5d693d9f23c20
Closes-Bug: #1552001

openstack/networking-cisco,Gitweijie/first_project,Tehsmash/networking-cisco,noironetworks/networking-cisco,Tehsmash/networking-cisco,Gitweijie/first_project,noironetworks/networking-cisco,openstack/networking-cisco