feat(rules): Client side information consequence in rules

**Summary**

With the release of the merchandising UI, the need to control UI aspects using the QR is growing and the rules API needs to expose fields to store information to perform specific client side tasks in a structured way.

The new consequence `consequence.renderingContent` contains a json object where each top level attribute is restricted to known use cases. The currently identified use cases are:
- Redirect
- Facet merchandising / ordering
- User defined data

Each top level excepted the `userData` one have a schema which is enforced and strict and customers can add metadata using the `userData` object:

```json
{
"condition": {
"anchoring": "is",
"pattern": "samsung"
},
"consequence": {
"renderingContent": {
"redirect": {
"url": "https://algolia.com/samsung" // required by the API
},
"facetMerchandising": {
"order": [ "brand", "price"] // required by the API
},
"userData": {
"callback": "displayBrand(samsung)" // optional field defined by user
}
}
}
}
```

This information will be returned in a structured way in the path `rules.consequence` of the search response:

```json
{
"hits": [...],
[...],
"query": "samsung",
"rules": {
"consequence": {
"renderingContent": [ // Array containing the content of matching rules
{
"facetMerchandising": {
"order": [
"brand",
"price"
]
},
"redirect": {
"url": "https://algolia.com/samsung"
},
"userData": {
"callback": "displayBrand(samsung)"
}
}
]
}
},
"userData": [ // Legacy userData
{
"myUserData": {}
}
]
}
```

Internal specs issue: [#152](https://github.com/algolia/algoliasearch-client-specs-internal/issues/152)

Inizia dall’issue interna delle specs collegata #152, quindi traccia come rules.consequence viene rappresentato nella risposta di ricerca del client Java. Il lavoro è completato quando il client espone renderingContent con le strutture redirect, facetMerchandising e userData descritte nell’issue, inclusi i campi obbligatori e la struttura della risposta indicati.

Scritto dal modello di indicizzazione a partire dal testo della issue.