Danube-delta

Fix
* Do not use bare except (4da7bb658fd16861fc49f6fc17577355cf54c8b7)
* Fix social media meta tags (293c20f173e0880992f5a7b64d768760dbb5ea72)

Feature
* Add settings for 'outdated article' warning (7a2278bb4040a4fedc4a7e53383cc336780f23ce)

Fix
* Correctly handle gif images (35c88a152223cef66e49fdfdf83df1ea18955d85)

Fix
* Bring back rounded corners for "about" images
* Fix broken "about" image on front page

Feature
* Use Twitter profile image if Gravatar is N/A

Fix
* 'blog photos' is now able to deal with spaces in photo filenames
* Migrate MD_EXTENSIONS to MARKDOWN setting

Feature
- Display Twitter account next to the author's name

Documentation
- Rewording --without-pip hint