Fixed sha1 unicode problem with py3k in cache.py
Merge remote-tracking branch 'upstream/master'
Added sys module to cache.py
Fixed remaining sha1 unicode py3 error ocurrencies
Decreased expiration time in test_remove_stale to work on slow Travis
Fixed test_remove_stale fail in py3k. Changed sys.version_info to util.py3k
Merge pull request #48 from C-Pro/master

Fixed tests to pass on python3