Added basic support for Romulus system.

This change includes:
    - Added support in tox.ini for running automation on Romulus
      system.
    - Added data/romulus.py file from skeleton which required for
      running sensor related test cases.
    - Fixed initializing inventory_root variable in data/romulus.py.

Resolves openbmc/openbmc-test-automation#639

Change-Id: I5afe5eb59a6fc41909982880def8b027871a994b
Signed-off-by: Rahul Maheshwari <rahulmaheshwari@in.ibm.com>
2 files changed