Update README.md documentation
Update README.md documentation

Changes:
   - Added new feature section.
   - Remove network section.
   - Other minor updates.

Change-Id: I11c139baa6cdd874ebe8b1093e7564c55924f8a8
Signed-off-by: George Keishing <bef0a9ecac45fb57611777c8270153994e13fd2e@in.ibm.com>

openbmc/openbmc-test-automation,openbmc/openbmc-test-automation