NSHM Unit tests

When running NSHM unit tests in pipeline, instead of running the hazard calculation in the junit test itself the hazard calculation is done by running a java class and writing out the results to JSON files.

src/test/java/gov/usgs/earthquake/nshmp/model/GenerateActual.java

@@ -10,6 +10,8 @@ import gov.usgs.earthquake.nshmp.model.NshmTestUtils.NshmModel;
  * Generate actual results to compare to expected results.
  *
  * Used in CI environment for faster unit tests.
+ *
+ * See nshms.gradle for generate tasks.
  */
 class GenerateActual {