Add steps to README.rst
Add steps to README.rst

Add tox to pip install.
Add step to run testr init

Change-Id: I10fd120d7757bc11695d064d488024e545655448
Authored-by: Chris Krelle <dd194f729e7b59c54085cae76b8200ec3f61813c@gmail.com>

rdo-management/tuskar,rdo-management/tuskar,tuskar/tuskar,rdo-management/tuskar