Updated log4j.properties to ignore jetty messages below WARN level

conf/log4j.properties

+# Set everything to be logged to the console
 log4j.rootCategory=INFO, console
 log4j.appender.console=org.apache.log4j.ConsoleAppender
 log4j.appender.console.layout=org.apache.log4j.PatternLayout
 log4j.appender.console.layout.ConversionPattern=%d{yy/MM/dd HH:mm:ss} %p %c{1}: %m%n
+
+# Ignore messages below warning level from Jetty, because it's a bit verbose
+log4j.logger.org.eclipse.jetty=WARN