Added rudimentary python 3 support. Passes all unittests.
Made the example plug-in Python 3 compatible.
pep8'd and pylint'd the areas of code changes in py3k branch.
Drop the version-specific check nonsense and go with the import fallback idiom. Even though Python 3.3 will allow you to import xml.etree.cElementTree directly, its marked as deprecated, so we might as well plan for the future.
Merge branch 'master' and resolve conflicts into python3_compatibility
replace Python version checks with try-import

as discussed in https://github.com/SoCo/SoCo/pull/42#issuecomment-26770403