Added some nice-to-have DB compound indexes
- Especially for comment queries during the PR post-process step
- Also some slight code cleanup and more explicit naming
Avatar fetching improvements
- Removed manual avatar scaling, using gravatar server scaling
- Increased avatar size storage on OSX, meaning notification avatars will look much better, especially on retina displays
- iOS avatar handling now uses JPEGs instead of PNGs for increased performance
Image files optimised for size