Es2

Implementing the ElasticSearch backend
It has to do with the max size that can be parsed by elasticsearch. For higher numbers this error is returned: "error": "ElasticsearchIllegalArgumentException[Failed to parse int parameter [size] with value [4294967293]]; nested: NumberFormatException[For input string: \"4294967293\"]; ",

I couldn't find documentation for a max size but (1<<31)-1 is the highest I was able to go, so we can bump it to that.