CQL execution in Java

Pass a CQL script file to the Engine, execute it, and get the results.

```java
Engine.setPatientSource(myPatientSource);
File script = new File("myMeasure.cql");
Results results = Engine.execute(script);
```

One test still failing (has to do with value sets in CMS146) but the "age" example works correctly, and I wanted to issue the pull request before the baselines diverge too far.