chnage serialization field names to be consistent with old format

model/src/main/java/lcsb/mapviewer/model/map/layout/ProjectBackground.java

@@ -11,6 +11,7 @@ import org.hibernate.annotations.Cascade;
 import org.hibernate.annotations.CascadeType;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 
 import lcsb.mapviewer.common.exception.NotImplementedException;
@@ -312,6 +313,7 @@ public class ProjectBackground implements Serializable {
     this.defaultOverlay = defaultOverlay;
   }
 
+  @JsonProperty("order")
   public int getOrderIndex() {
     return orderIndex;
   }
@@ -332,6 +334,7 @@ public class ProjectBackground implements Serializable {
     }
   }
 
+  @JsonProperty("images")
   public Set<ProjectBackgroundImageLayer> getProjectBackgroundImageLayer() {
     return backgrounds;
   }

rest-api/src/main/java/lcsb/mapviewer/api/projects/ProjectRestImpl.java

@@ -804,7 +804,7 @@ public class ProjectRestImpl extends BaseRestImpl {
           throw new QueryException("name cannot be empty");
         }
         background.setName((String) value);
-      } else if (key.equalsIgnoreCase("orderIndex")) {
+      } else if (key.equalsIgnoreCase("order")) {
         background.setOrderIndex(parseInteger(value));
       } else if (key.equalsIgnoreCase("defaultOverlay")) {
         background.setDefaultOverlay(parseBoolean(value));

web/src/test/java/lcsb/mapviewer/web/ProjectControllerIntegrationTest.java

@@ -986,19 +986,19 @@ public class ProjectControllerIntegrationTest extends ControllerIntegrationTest
         fieldWithPath("progress")
             .type(JsonFieldType.NUMBER)
             .description("generating images progress information (in %)"),
-        fieldWithPath("orderIndex")
+        fieldWithPath("order")
             .type(JsonFieldType.NUMBER)
             .description("order used when listing all backgrounds"),
-        fieldWithPath("projectBackgroundImageLayer[].id")
+        fieldWithPath("images[].id")
             .type(JsonFieldType.NUMBER)
             .ignored(),
-        fieldWithPath("projectBackgroundImageLayer[].projectBackground.id")
+        fieldWithPath("images[].projectBackground.id")
             .type(JsonFieldType.NUMBER)
             .ignored(),
-        fieldWithPath("projectBackgroundImageLayer[].directory")
+        fieldWithPath("images[].directory")
             .type(JsonFieldType.STRING)
             .description("directory where background tiles are located"),
-        fieldWithPath("projectBackgroundImageLayer[].model.id")
+        fieldWithPath("images[].model.id")
             .type(JsonFieldType.NUMBER)
             .description("(sub)map for which images are described"),
         fieldWithPath("defaultOverlay")