We do not need tox_install.sh, pip can handle constraints itself
and install the project correctly. Thus update tox.ini and remove
the now obsolete tools/tox_install.sh file.
This follows https://review.openstack.org/#/c/508061 to remove
tools/tox_install.sh.
Change-Id: Iff0494f5fc46a57792035aaf44d391cbafa0df87
Running `tox -ecover` does not generate the coverage report.
Instead the following is displayed to the user:
No coverage report, but warnings instead:
Coverage.py warning: Module networking-dpm was never imported.
This patch set fixes the problem.
Change-Id: Ia2f88e4899536e935e243200093d9855f2c56dbc