Memory Capped LRU Cache

This package provides an LRU string -> []byte cache with a few nice features:

• Support for evicting the least recently used items to reduce the amount of data referenced by the cache
  • Both synchronous and asynchronous eviction supported
• Setting TTL on items with lazy eviction
• Good performance
  • 176 ns/insert over 10M inserts with 8 4GHz cores contending (BenchmarkConcurrentInserts)

This cache is ideal for items of roughly uniform size with a TTL.