Log Message:
py-relatorio: updated to 0.8.1

0.8.1:
* Add support for Python 3.7
* Escape invalid XML characters
* Enforce closing tag to be the same directive as the opening
* Use compression for zip file
* Write mimetype as first file of the zip file

0.8.0:
* Do not guess_type on styled cell content
* Remove type attributes when guessing type
* Add support for Python 3.6
* Remove soft-page-break

0.7.1:
* Remove warning when import plugin fails
* Apply the guess type function on the correct node
* Fix guess_type for date and datetime

0.7.0:
* Replace hard-coded extensions by mimetypes guess
* Add more guess types: 'boolean', 'date', 'time' and 'void'
* Add support for Flat OpenDocument

0.6.4:
* Use StringIO instead of BytesIO for TextSerializer result