ILP Store Wrapper

> Synchronous wrapper around ILP store

The constructor takes an ILP store.

``js
const wrappedStore = new StoreWrapper(store)
`

- .load(key) -> Promise will read a key asynchronously into the cache.
- .get(key) -> value will synchronously read from the cache.
- .set(key, value) -> null will synchronously write to the cache and queue a write to the store (with order guaranteed).
- .delete(key) -> null will synchronously delete from the cache and queue a delete to the store (with order guaranteed).
- .setCache(key, value) -> null` will synchronously write to the cache and NOT queue any write to the store.