Fix some compile issues

hapi-fhir-structures-dstu2.1/src/main/java/org/hl7/fhir/dstu2016may/metamodel/Manager.java

@@ -22,8 +22,9 @@ public class Manager {
     switch (format) {
     case JSON : return new JsonParser(context);
     case XML : return new XmlParser(context);
+    default:
+      throw new IllegalArgumentException("Unknown type: " + format);
     }
-    return null;
   }
   
 }

hapi-fhir-structures-dstu2.1/src/main/java/org/hl7/fhir/dstu2016may/utils/FHIRPathEngine.java

@@ -1095,6 +1095,7 @@ public class FHIRPathEngine {
       return result;
     case Concatenate:
       result = new TypeDetails(CollectionStatus.SINGLETON, "");
+		return result;
     case Plus:
       result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType("integer") && right.hasType("integer"))

hapi-fhir-structures-dstu2.1/src/main/java/org/hl7/fhir/dstu2016may/utils/JsonTrackingParser.java

@@ -364,6 +364,8 @@ public class JsonTrackingParser {
 				break;
 			case Eof : 
 				throw lexer.error("Unexpected End of File");
+			default:
+				break;
 			}
 			next();
 		}
@@ -405,6 +407,8 @@ public class JsonTrackingParser {
         break;
 	    case Eof : 
 	    	throw lexer.error("Unexpected End of File");
+       default:
+			break;
 	    }
 	    next();
 	  }

hapi-fhir-structures-dstu2.1/src/main/java/org/hl7/fhir/dstu2016may/validation/InstanceValidator.java

@@ -137,10 +137,13 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
 			switch (bpWarnings) {
 			case Error:
 				rule(errors, invalid, line, col, literalPath, test, message);
+				break;
 			case Warning:
 				warning(errors, invalid, line, col, literalPath, test, message);
+				break;
 			case Hint:
 				hint(errors, invalid, line, col, literalPath, test, message);
+				break;
 			default: // do nothing
 			}
 		}
@@ -1607,6 +1610,8 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
 				else if (itemType.equals("integer")) checkOption(errors, answer, ns, qsrc, qItem, "integer");
 				else if (itemType.equals("string")) checkOption(errors, answer, ns, qsrc, qItem, "string", true);
 				break;
+			default:
+				break;
 			}
 			validateQuestionannaireResponseItems(qsrc, qItem.getItem(), errors, answer, stack, inProgress);
 		}

hapi-fhir-structures-dstu3/src/main/java/org/hl7/fhir/dstu3/utils/FHIRPathEngine.java

@@ -1193,6 +1193,7 @@ public class FHIRPathEngine {
       return result;
     case Concatenate:
       result = new TypeDetails(CollectionStatus.SINGLETON, "");
+      return result;
     case Plus:
       result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType(worker, "integer") && right.hasType(worker, "integer"))