absolute import

[likang]

It is very likely to get package conflict when using relative import like 'from error import *' in python3, so I think it's time to use absolute import 😄

here is an example:
.
├── __init__.py
├── error.py
└── my_app.py (only one line in this file import voluptuous)

then if you run python3 my_app.py will get an error:

AttributeError: module 'error' has no attribute 'Invalid'

[coveralls]

Coverage decreased (-0.08%) to 95.309% when pulling 33fc381 on likang:master into f24fc02 on alecthomas:master.