Merge pull request #4 from petrjasek/master

Prevent overriding __ attributes.
Bump version to 0.2.1.
Prevent overriding of '__' attributes.
tox and Python 3.4
trove qualifiers for python versions.
Copyright 2014
v0.2.1 release date
fix trove qualifiers
tox and Python 3.4 in README too.
Duplicate short description.