fix logging, to send error logs to stderr

Author: stuzart

pom.xml

@@ -5,7 +5,7 @@
 	<artifactId>simple-spreadsheet-extractor</artifactId>
 	<name>POI Based Spreadsheet parser</name>
 	<description>Simple command line app that translates a Spreadsheet file to an XML document</description>
-        <version>0.18.0</version>
+        <version>0.18.1</version>
 	<dependencies>
 		<dependency>
 			<groupId>org.apache.poi</groupId>

src/main/resources/log4j.properties

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration>
+  <Properties>
+    <Property name="pattern">
+    	[%d{yyyy-MM-dd HH:mm:ss.SSS}][%highlight{%-5level}][%t][%logger] %msg%n
+    </Property>
+  </Properties>
+  <Appenders>
+    <Console name="stdout" target="SYSTEM_OUT"> 
+      <PatternLayout pattern="${pattern}"/>
+      <ThresholdFilter level="ERROR" onMatch="DENY" onMismatch="ACCEPT"/>
+    </Console>
+    <Console name="stderr" target="SYSTEM_ERR"> <!-- 2 -->
+      <PatternLayout pattern="${pattern}"/>
+      <ThresholdFilter level="ERROR" onMatch="ACCEPT" onMismatch="DENY"/>
+    </Console>
+  </Appenders>
+  <Loggers>
+    <Root level="ERROR">
+      <AppenderRef ref="stdout"/>
+      <AppenderRef ref="stderr"/>
+    </Root>
+  </Loggers>
+</Configuration>