Merge pull request #1913 from ebean-orm/feature/MaxMin

Change to use @Aggregation as meta annotation - support newly added @Max, @Min, @Avg annotations

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationFields.java

@@ -315,11 +315,7 @@ public class AnnotationFields extends AnnotationParser {
 
     Aggregation aggregation = get(prop, Aggregation.class);
     if (aggregation != null) {
-      prop.setAggregation(aggregation.value());
-    }
-    Sum sum = get(prop, Sum.class);
-    if (sum != null) {
-      prop.setAggregation("sum(" + prop.getName() + ")");
+      prop.setAggregation(aggregation.value().replace("$1", prop.getName()));
     }
 
     Version version = get(prop, Version.class);

src/test/java/org/tests/model/aggregation/DMachineStatsAgg.java

@@ -1,6 +1,7 @@
 package org.tests.model.aggregation;
 
 import io.ebean.annotation.Aggregation;
+import io.ebean.annotation.Max;
 import io.ebean.annotation.Sum;
 import io.ebean.annotation.View;
 
@@ -24,7 +25,7 @@ public class DMachineStatsAgg {
   @Aggregation("sum(hours)") // which is the same as: @Sum
   long hours;
 
-  @Aggregation("max(rate)")
+  @Max
   BigDecimal rate;
 
   /**