Lucene.Net.Core.Util.DoubleBarrelLRUCache refactor: removed duplicate ClonableKey class and made DoubleBarrelLRUCache<TKey, TValue> subclass DoubleBarrelLRUCache.
Lucene.Net.Core.Util.DoubleBarrelLRUCache refactor: removed duplicate ClonableKey class and made DoubleBarrelLRUCache<TKey, TValue> subclass DoubleBarrelLRUCache.

jeme/lucenenet,apache/lucenenet,sisve/lucenenet,NightOwl888/lucenenet,apache/lucenenet,NightOwl888/lucenenet,apache/lucenenet,NightOwl888/lucenenet,laimis/lucenenet,apache/lucenenet,laimis/lucenenet,sisve/lucenenet,NightOwl888/lucenenet,jeme/lucenenet,jeme/lucenenet,jeme/lucenenet