Support InCodeSystem/AnyInCodeSystem

[cmoesel]

The InCodeSystem/AnyInCodeSystem operations allows authors to determine if a String, Code, or Concept is in a given CodeSystem, or if a List of the previously mentioned types overlaps the codes in a given CodeSystem (see Appendix B).

CQL Execution currently only supports code equality and equivalence (code to code). CQL Execution does not currently have any way of expanding a CodeSystem or querying a CodeSystem. Supporting InCodeSystem would require more advanced terminological support, especially since some code systems are quite large!