append .tox to avoid going in there

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
make sure we don't hard code the path for py.test

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
just use python 2.7 for now

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
tell tox to use site-packages

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
tell py.test that we want teuthology stuff only

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
move the sitepackages to testenv section

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>