allow for both valid query strings

since dict is unordered, the resulting query string
params could be in any order as well.
Support python 2.6

Switch a few 2.7-only bits to be 2.6 compatible, since many
developers are still on 2.6, and many existing deployments
assume 2.6.
Merge pull request #2 from brfitzgerald/support-python-2.6

Support Python 2.6
Merge pull request #3 from brfitzgerald/fix-join-url-params

Fix test to not assume guaranteed order in dict