Fix the logLevelFilter with lazy loading

Author: Danny Brain

lib/appenders/logLevelFilter.js

@@ -1,4 +1,5 @@
 var levels = require('../levels');
+var log4js = require('../log4js');
 
 function logLevelFilter (levelString, appender) {
     var level = levels.toLevel(levelString);
@@ -10,10 +11,11 @@ function logLevelFilter (levelString, appender) {
 }
 
 function configure(config) {
-    var appender = config.makers[config.appender.type](config.appender);
+    log4js.loadAppender(config.appender.type);
+    var appender = log4js.appenderMakers[config.appender.type](config.appender);
     return logLevelFilter(config.level, appender);
 }
 
 exports.name = "logLevelFilter";
 exports.appender = logLevelFilter;
-exports.configure = configure;
+exports.configure = configure;