Cache

• Fixed reference eviction when used with a broken executor (JDK-8274349)
• Reduced the entry overhead by 8 bytes when using weak or soft values
• Suppressed log warnings if a future is cancelled or times out (#597)
• Fixed Map.entrySet.contains(o) to use reference equality
• Fixed early expiration of in-flight async loads (#625)

JCache

• close() will now shutdown the executor and wait for in-flight loads to finish