[PATCH] tox: Don't create '.pyc' files

[Stephen Finucane]

On 03 Sep 21:08, Stephen Finucane wrote:
> In '8e58c29', code was added to delete '.pyc' files. However, this was
> later reverted in '9fd161' due to the increase in run time that this
> incurred. However, the need to avoid stale '.pyc' files still exists.
> To resolve this, add the 'PYTHONDONTWRITEBYTECODE' environment option
> to disable generation of these files. This includes a slight
> performance increase.
> 
> Signed-off-by: Stephen Finucane <stephenfinucane at hotmail.com>

Merged.