Implementation of the `ShardedCache`

[scalalang2]

Motivation

refer : elastic/go-freelru

They provides ShardedLRU which provides sharded, concurrency-safe implementation but it uses an approximate LRU algorithm.

[ccoVeille]

The issue was closed, but what PR or commit implemented it?

Having the reference would be better I think

[scalalang2]

This was unintentionally closed, I repoened this, thx : )