* better logging
* added suppot for optimizaton-cache (S3)
* fixed temp files being left on disk after image conversion errors
* fixed favicon conversion to png
* fixed crash on empty text comment
* fixed some links not working (129)
* improved plain text links support.
* added support for images in comments
* updated dependencies (mistune, beautifulsoup, Pillow)
* fixed missing index in ZIM
* fixed gif to png conversion
* better filetype checking: fallback to magic no known filetype found in header
* replaced filemagic with python-magic