Incorporated the review comments.

Changed Following:
1. Moved toragent folder under compute
2. Merged common.py for toragent with setup.py

Adding proviosning support for TSN and Tor Agent.

Adding the proviosning support for tsn and tor agent. Relavant fab task commited under
contrail-fabric-utils. This will make required config change and addition of
config file to enable tsn and toragent functionality.
Closes-bug:1405758
Change-Id: If49150f5cb22b922f0e4ed6adb608361a9c622b8