Fix some video download edge cases: (#776) Fix downloading of sidecar videos if --no-pictures is set (#763) Fix downloading of videos that do not have a thumbnail image (#773) Fix support for (outdated) Python version 3.5 prior to 3.5.4 (#765, #777) Fix FileExistsError (Windows only) when replacing an already-downloaded picture (#769, #775) Improve message that is printed upon 429 response