Add log4j logging and bridge (#383)

WIP just showing that something works to log debug level

metafix-runner/build.gradle

@@ -30,6 +30,9 @@ dependencies {
   implementation "org.metafacture:metafacture-xml:${versions.metafacture}"
   implementation "org.metafacture:metafacture-yaml:${versions.metafacture}"
   implementation "org.metafacture:metamorph:${versions.metafacture}"
+  runtimeOnly 'org.apache.logging.log4j:log4j-core'
+  implementation 'org.apache.logging.log4j:log4j-1.2-api:2.9.1'
+  implementation 'ch.qos.logback:logback-classic:1.3.14'
 
   implementation('org.antlr:antlr-runtime') {
     version { strictly versions.antlr }

metafix/src/main/resources/log4j.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE log4j:configuration SYSTEM "http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/xml/doc-files/log4j.dtd">
+
+<log4j:configuration>
+    <appender name="stdout" class="org.apache.log4j.ConsoleAppender">
+        <layout class="org.apache.log4j.PatternLayout">
+            <param name="ConversionPattern"
+                value="%-5p [%t] [%c{1}] %m%n" />
+        </layout>
+    </appender>
+
+    <root>
+        <priority value="DEBUG" />
+        <appender-ref ref="stdout" />
+    </root>
+
+</log4j:configuration>
+