Allow sending IncreaseDecreaseType directly to DimmerItem (#3116)

Signed-off-by: Cody Cutrer <cody@cutrer.us>

bundles/org.openhab.core/src/main/java/org/openhab/core/library/items/DimmerItem.java

@@ -51,6 +51,10 @@ public class DimmerItem extends SwitchItem {
         internalSend(command);
     }
 
+    public void send(IncreaseDecreaseType command) {
+        internalSend(command);
+    }
+
     @Override
     public List<Class<? extends State>> getAcceptedDataTypes() {
         return ACCEPTED_DATA_TYPES;