Simple Thread-safe in memory LRU cache for ruby. Dev in progress

1. To init, cache_store = MemoryCache::MemoryCacheStore.new
2. cache_store.write('key1', 'value1') => return true or false
3. cache_store.read('key1')
4. cache_store.delete('key1')
5.cache_store.clear => flushes the store

# LFU cache:
  
  1. To init, cache_store = MemoryCache::MemoryLfuCacheStore.new
  2. cache_store.write('key1', 'value1') => return true or false
  3. cache_store.read('key1')
  4. cache_store.delete('key1')
  5.cache_store.clear => flushes the store