Ordering of handler execution

There should be a way to organize a queue (aka async transactions) of handlers using `deeplinks` as an orchestrator.

```js
const delay = (time) => new Promise(res => setTimeout(() => res(null), time));

while (true) {
const {data: inProgres} = await deep.select({
from: { type_id: {_eq: Post}, id: {_lt: currentId} },
type_id: { _eq: Then },
to: {
_not: {
out: {
type_id: { _in: [Resolved, Rejected] }
}
}
}
});
if (!inProgres.length) break;
await delay(1000);
}
```

At the moment, we are forced to use similar code to organize queue between handlers, that generates multiple queries, and these can be avoided.