New features

• Includes a CacheProvider class to create commonly used caches
• Includes a Playground to quickly test Carlos and custom cache architectures
• includes a new switchLevels function to have multiple cache lanes

Enhancements

• Improves DiskCacheLevel and MemoryCacheLevel by having protocol-based keys
• Defines safer Transformers (either OneWayTransformer or TwoWayTransformer) that return Optionals. If a conversion fails, set operations silently fail and get operations fail with a meaningful error.
• Extends the conditioned function and the <?> operator to support fetch closures
• Improves the code documentation

Bugfixes

• Fixes an issue where the NetworkFetcher would not correctly handle multiple get requests for the same URL