Allow parallel evaluation for big patient lists

[Dogacel]

https://github.com/cqframework/clinical-reasoning/blob/710efbe154cd2239a70cc63ea2ef54802db4a27a/cqf-fhir-cr/src/main/java/org/opencds/cqf/fhir/cr/measure/common/MeasureEvaluator.java#L300

Here, we are running a sequential list over our list of patients. I think we should have some setting to allow parallelising each patient's measure calculation, moreover this parallelisation factor should be configurable.

In cases where we want to evaluate measures over 100,000+ patients, this would help quite a bit.