Add 'setup.cfg' to allow persistent configuration of nose options.
One extension per line.
Automate testing supported Python versions, coverage, Sphinx docs w/ tox.
Get all testenvs running under tox.
Drop use of setup.cfg.

Pass coverage-related args to nose explicitly.
(Really) pass coverage-related args to nose explicitly.
Convert commented line to a TODO.
Merge pull request #127 from tseaver/expand_testing

Set up local machine test automation with tox.