tox-2.1.0: passenv refinements

[holger krekel]

I just released tox-2.1.0 to pypi which streamlines the "passenv"
behaviour to accomodate a number of issues, see the changelog below.

You can find docs for the virtualenv based test runner here:

    http://tox.testrun.org

have fun,

holger


2.1.0
-----

- fix issue258, fix issue248, fix issue253: for non-test commands 
  (installation, venv creation) we pass in the full invocation environment.

- remove experimental --set-home option which was hardly used and
  hackily implemented (if people want home-directory isolation we should
  figure out a better way to do it, possibly through a plugin)

- fix issue259: passenv is now a line-list which allows to intersperse
  comments.  Thanks stefano-m.

- allow envlist to be a multi-line list, to intersperse comments
  and have long envlist settings split more naturally.  Thanks Andre Caron.

- introduce a TOX_TESTENV_PASSENV setting which is honored
  when constructing the set of environment variables for test environments.
  Thanks Marc Abramowitz for pushing in this direction.