IsAggregationTypeNumerical(string) blows up if no AggregationType is set...

... on facet, so require AggregationType if an aggregation is specified that is not AggregationType.None and AggregationType.Count

Upgrading to RavenDB 3 from 2.5, we have facets which specify a Min and Max aggregation but do not specify an AggregationType, this causes an exception on line 351 of FacetedQueryRunner because *aggregationType* is null.

I assume you want to throw an exception if no AggregationType is specified as per the changeset, but I notice that no exception is thrown from line 353 of FacetedQueryRunner if the aggregation type cannot be found. Maybe this should also throw, however I don't fully understand the significance of returning false from IsAggregationTypeNumerical when the AggregationType is actually numerical.