Support partial deployments

[nchamo]

As of today, new entities need to be deployed all at once. Content files need to be already uploaded and in use by another entity, or they need to be uploaded in the same operation that creates the new entity.

This works for most cases, but there are some entities (such as scenes) that could be really big in terms of size. This has caused problems in the past. For example, cloudflare has a maximum size per POST request.

The idea here would be to allow "partitioned deployments". These would be deployments that can be deployed in smaller part. The idea would be that many HTTP operations can result in one deployment.

If we go with this approach, we would need to be careful with a few things:

• Make sure that this cannot be used by attackers, so the same size limit that applies to "full" deployments need to be enforced
• Deployments take into account the entity's timestamp to determine if they are valid or not. We would need to take this new operation into account and make sure we are not breaking anything

Once this is merged and released, we would need to change the catalyst client to use this new operation by default. If it doesn't exist, please create an issue for that once this is merged.