private boolean isNumeric(AttributesConfig.Attribute.Datatype.Enum dt) {
        return  dt == AttributesConfig.Attribute.Datatype.DOUBLE ||
                dt == AttributesConfig.Attribute.Datatype.FLOAT ||
                dt == AttributesConfig.Attribute.Datatype.INT8 ||
                dt == AttributesConfig.Attribute.Datatype.INT16 ||
                dt == AttributesConfig.Attribute.Datatype.INT32 ||
                dt == AttributesConfig.Attribute.Datatype.INT64;
    }
Validates that the attribute given as match-phase override is actually a valid numeric attribute
with fast-search enabled.

@author baldersheim
container-search/src/main/java/com/yahoo/search/searchers/ValidateMatchPhaseSearcher.java