Merge branch 'release/0.5.1' into develop
Import six
Merge pull request #16 from kostajh/develop

Import six
PEP8.
Run tests on both normal and experimental implementations.
Note support for py3.3
PEP8.
Try to support skiptest on py2.6.
Spare them the spam.
Added forgotten import.
Oh.  This is a lot easier.
Compatibility between experimental and normal modes.
Delete modified field from task
Merge pull request #17 from kostajh/develop

Fix test_updating_task
Do not replace slashes when in experimental mode
Merge pull request #18 from kostajh/develop

Do not replace slashes when in experimental mode
Be more gentle with the timestamp test.
Add failing test against experimental mode.
Merge branch 'develop' of github.com:ralphbean/taskw into develop
Skip experimental tests of taskwarrior version is too low.