fly/v42

Deploy a7ac3f5

Diff: fly/v40...fly/v42

• irb prompt polish
• Handle YouTube 500 errors.
• bundle update
• Instagram: Handle posts with missing caption.
• Twitch: Handle /schedule URLs.
• Twitch: Fix <author> on game feeds.
• Twitch: Support new /directory/category/ URLs to look up game feeds.