`Implies` operator in CMS144

[birick1]

There is an outstanding ticket for implementing the implies operator in the engine at #158.

I don't think any measure previously has used the operator. That changed recently with the measure CMS144 now looking to use the implies operator.

In addition, the ELM translator did not support translation of implies when #158 was created, but it does now. Attaching CMS144 and test cases for use in implementing the implies feature. CMS144FHIR-v1.3.000-FHIR4 (2).zip CMS144FHIR-v1.3.000-FHIR4-TestCases.zip