Remove decode('UTF-8') since it removes the UTF-8 encoding

This should fix GH-226.

Removing `decode('UTF-8')` seems to work. I think the default encoding should be UTF-8 already based on the encoding header at the top of the python file `# -*- coding: utf8 -*-`. In addition the charset is UTF-8 in the generated HTML file as well as the sqlite3 database.

I tested various languages using text from this site http://www.columbia.edu/~kermit/utf8.html.