## DataItem
```js
{
    hash: SHA3, // SHA3-384 
    treeHash: SHA3, // random hash defined on the root of the tree,
    parentHash: SHA3,
    lvl: int, //the level above the tree root,
    creator: SHA3, // the creator of this link for diff between sys and usr,
    created: unix timestamp, // with ms,
    importance: int, // the importance of the data - higher is more important - will be used to decide if unimportant data will be sacrificed for the sake of the reliability of more important data
    content: byteArray || null,
    deleted: bool
    hashIfDeleted: SHA3


    lastChecked: unix timestamp, // with ms,
    readingErrors: int,

    extras: {...}, // json
}
```