Merge pull request #8 from lnielsen-cern/master

Change list diff behavior
Add tox.ini for simultanous py26, 27, and 33 test
Fix issue with patching lists

* Fixes an issue when removing elements from a list during patching,
  caused by wrong iteration order.
Fix issue with differences in type

* Fixes an issue where a dictionary having two different types of
  values for the same key would cause an error.
Add Travis conf