506 avoid data cloning

[idruzhitskiy]

closes #506

[ikopylov]

More places:
https://github.com/qoollo/bob/blob/master/bob/src/cluster/simple.rs#L54
https://github.com/qoollo/bob/blob/master/bob/src/cluster/quorum.rs#L151

[ikopylov]

Please, fix warnings in bob-backend/src/pearl/data.rs

[idruzhitskiy]

More places: https://github.com/qoollo/bob/blob/master/bob/src/cluster/simple.rs#L54 https://github.com/qoollo/bob/blob/master/bob/src/cluster/quorum.rs#L151

Both are caused by BobClient needing ownership of data

[ikopylov]

Tests failing. Please, fix them

[ikopylov]

Can data be passed by reference here? (in quorum.rs):

impl Cluster for Quorum {
    async fn put(&self, key: BobKey, data: BobData) -> Result<(), Error> {
        self.put_at_least(key, data).await
    }

[ikopylov]

LGTM