unittest discover is not available in Python 2.6. Revert to 7f29234754be0f7d9a248ac0ef045d9306858eac.
Updated comment
Added development requirements.
Updated six version.
Update requirements.txt
Merge pull request #192 from kurniliya/fix-tox-py26

Fix tox py26 env (closes #191)
Install cov-core in dev (see bootstrap.sh) and test (tox, Travis) envs. Required by coverage plugin
Our style is PEP8
Make test also work on Windows that uses backslash as path delimiter
Merge pull request #190 from kurniliya/fix-ci

Fix failing functional test for coverage plugin
Fixed missing return that broke test discovery.
Also fixed test that would fail on some setups
Fix pkg1 test failures.

Renamed egg test package from pkg1 to pkgegg as the sys.path shenanigans
were making other tests fail.
Fixed eggdiscovery documentation warning
Added eggdiscovery import in test module to prevent Travis failures
Absolute import of discovery module to fix Travis failures
Fixed py3 build