Use docvalue for range faceting in JSON facet API

Range faceting in JSON facet API has only one implementation. In the implementation, all buckets are allocated and then range queries are executed for all the buckets. Therefore, memory usage and computational cost of range facet can be very high if range is wide and gap is narrow.

I think range faceting in JSON facet should have the implementation which uses DocValues instead of inverted indices. By scanning DocValues, we can execute range facets much more efficiently especially when the number of buckets is large.