Makefile and python cleanups.

Makefile
--------
  o Add std copyright notice header
  o Update to use repo:onf-make to support virtualenv, etc makefile targets.
  o Update help to display a static text block.  Grep for strings prefixed
    by '##' can become confused and display 'Makefile' instead of target name.

tox.ini
-------
  o Update to also support python 3.10+

Change-Id: Id8183ad03df252c81631a8c5ef4f08fe23d0ada5
8 files changed