* vendor: Add bimg image processing library
bimg is MIT licensed. It depends on the C library libvips which is LGPL
v2.1+ licensed. libvips must be installed separately.
* mediaapi: Add YAML config file support
* mediaapi: Add thumbnail support
* mediaapi: Add missing thumbnail files
* travis: Add ppa and install libvips-dev
* travis: Another ppa and install libvips-dev attempt
* travis: Add sudo: required for sudo apt* usage
* mediaapi/thumbnailer: Make comparison code more readable
* mediaapi: Simplify logging of thumbnail properties
* mediaapi/thumbnailer: Rename metrics to fitness
Metrics is used in the context of monitoring with Prometheus so renaming
to avoid confusion.
* mediaapi/thumbnailer: Use math.Inf() for max aspect and size
* mediaapi/thumbnailer: Limit number of parallel generators
Fall back to selecting from already-/pre-generated thumbnails or serving
the original.
* mediaapi/thumbnailer: Split bimg code into separate file
* vendor: Add github.com/nfnt/resize pure go image scaler
* mediaapi/thumbnailer: Add nfnt/resize thumbnailer
* travis: Don't install libvips-dev via ppa
* mediaapi: Add notes to README about resizers
* mediaapi: Elaborate on scaling libs in README
