Resolve TODO (add isDevelopment method as default method in PluginManager)

pf4j/src/main/java/org/pf4j/AbstractPluginManager.java

@@ -913,11 +913,6 @@ public abstract class AbstractPluginManager implements PluginManager {
         }
     }
 
-    // TODO add this method in PluginManager as default method for Java 8.
-    protected boolean isDevelopment() {
-        return RuntimeMode.DEVELOPMENT.equals(getRuntimeMode());
-    }
-
     /**
      * @return true if exact versions in requires is allowed
      */

pf4j/src/main/java/org/pf4j/PluginManager.java

@@ -154,6 +154,13 @@ public interface PluginManager {
      */
     RuntimeMode getRuntimeMode();
 
+    /**
+     * Returns {@code true} id the runtime mode is {@code RuntimeMode.DEVELOPMENT}.
+     */
+    default boolean isDevelopment() {
+        return RuntimeMode.DEVELOPMENT.equals(getRuntimeMode());
+    }
+
     /**
      * Retrieves the {@link PluginWrapper} that loaded the given class 'clazz'.
      */