facets: counts aren't as logical as they could be when multiple aggregates are used

[mish15]

If two sets of facets are used that display counts, when one of these adds a filter, the counts do not update on the other facets, which is not representative of the state. Currently this is done because if they did update for the facet being changed, all the values would go to zero, but this is not so logical if multiple facets are involved.

cc @jrhodes-sitback