scopes are less leaky in python3…

…so i made the assignment of x explicit.

to be honest: i didn’t understand that part at all, so exploiting the leak was probably never a good idea in the first place.
Fix wrong error message on optional key dict val
Merge pull request #10 from thomaserlang/master

Fixed wrong error message on optional key dict validate
Fix doctest
Make guard decorator private

Since it is an experimental feature.
Bump version to 0.1.2
Add MANIFEST.in to have README on PyPI
Convert README.md to README.rst
Make README.rst show on PyPI
Update version in README
Setup tox and travis
Test README.rst on Python 2.7
Merge pull request #6 from flying-sheep/patch-2

scopes are less leaky in python3…
Remove guard decorator until better times
Attempt to port tests to Python 3
Merge remote-tracking branch 'origin/master'
This fixes py26, py27 tests; don't know why
Announce Python 3 support
Fix some .rst formatting
Implement #9 (see also #11)