Moved polyglossia/babel definitions to before biblatex; otherwise biblatex fails with xetex.
Fixed typo.
Use biblatex-chicago instead of biblatex.
Revert "Use biblatex-chicago instead of biblatex."

This reverts commit a0ea58bc2ed43a09f6c349ad20a0b1ee2791a75b.
Merge pull request #70 from bluebirch/master

Fix polyglossia/biblatex problem with xelatex