Bugfix for 48b39e4978bec3b0e11cfc840644653235dd1388
Bugfix for 48b39e4978bec3b0e11cfc840644653235dd1388

Commit referenced above contained a trailing comma in the
"Authorization" dict key:
https://github.com/urschrei/pyzotero/commit/48b39e4978bec3b0e11cfc840644653235dd1388#diff-2bcadae5244731b9e9f771fd5d0561d1R222

This caused the value to be converted to a tuple, causing auth to fail.

DrGo/pyzotero,urschrei/pyzotero