added at() as an alias for makeLoggingEventBuilder()

Signed-off-by: Ceki Gulcu <ceki@qos.ch>

slf4j-api/src/main/java/org/slf4j/Logger.java

@@ -113,6 +113,17 @@ public interface Logger {
         }
     }
 
+    /**
+     * An alias for {@link #makeLoggingEventBuilder}. 
+     * 
+     * @since 2.0
+     */
+    default public LoggingEventBuilder at(Level level) {
+        return makeLoggingEventBuilder(level);
+    }
+
+    
+    
     /**
      * Returns whether this Logger is enabled for a given {@link Level}. 
      *