Migrated logging to log4j2 and adapted java.util.logging to log4j.

Change-Id: I587a8f0252714e17ec70e0f9eb5db63aca292b5f
diff --git a/core/pom.xml b/core/pom.xml
index 45780a9..3e09cee 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -80,13 +80,13 @@
 				rest tests -->
 			<!-- <plugin>
 				<groupId>org.apache.maven.plugins</groupId>
-				<artifactId>maven-jar-plugin</artifactId>
-				<version>3.0.2</version>
+				<artifactId>maven-source-plugin</artifactId>
+				<version>3.0.1</version>
 				<executions>
 					<execution>
-						<phase>package</phase>
+						<id>attach-sources</id>
 						<goals>
-							<goal>test-jar</goal>
+							<goal>jar</goal>
 						</goals>
 					</execution>
 				</executions>
@@ -183,12 +183,29 @@
 			<version>${jersey.version}</version>
 			<scope>test</scope>
 		</dependency>
+		<!-- EM: Logging -->
 		<dependency>
-			<groupId>org.slf4j</groupId>
-			<artifactId>slf4j-log4j12</artifactId>
-			<version>1.7.25</version>
+			<groupId>org.apache.logging.log4j</groupId>
+			<artifactId>log4j-api</artifactId>
+			<version>2.11.0</version>
 		</dependency>
 		<dependency>
+			<groupId>org.apache.logging.log4j</groupId>
+			<artifactId>log4j-core</artifactId>
+			<version>2.11.0</version>
+		</dependency>
+		<dependency>
+		    <groupId>org.apache.logging.log4j</groupId>
+		    <artifactId>log4j-slf4j-impl</artifactId>
+		    <version>2.11.0</version>
+		</dependency>
+		<dependency>
+		    <groupId>org.apache.logging.log4j</groupId>
+		    <artifactId>log4j-jul</artifactId>
+		    <version>2.11.0</version>
+		</dependency>
+		
+		<dependency>
 			<groupId>junit</groupId>
 			<artifactId>junit</artifactId>
 			<version>4.12</version>
@@ -212,14 +229,22 @@
 					<groupId>org.eclipse.jetty</groupId>
 					<artifactId>jetty-servlet</artifactId>
 				</exclusion>
-				<exclusion> 
-			        <groupId>org.slf4j</groupId>
-			        <artifactId>slf4j-log4j12</artifactId>
-			    </exclusion>
-			    <exclusion> 
-			        <groupId>log4j</groupId>
-			        <artifactId>log4j</artifactId>
-			    </exclusion>
+				<exclusion>
+					<groupId>org.slf4j</groupId>
+					<artifactId>slf4j-api</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>org.slf4j</groupId>
+					<artifactId>slf4j-log4j12</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>log4j</groupId>
+					<artifactId>log4j</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>log4j</groupId>
+					<artifactId>apache-log4j-extras</artifactId>
+				</exclusion>
 			</exclusions>
 		</dependency>
 
@@ -229,8 +254,6 @@
 			<version>3.21.0</version>
 		</dependency>
 
-		
-
 		<dependency>
 			<groupId>org.apache.commons</groupId>
 			<artifactId>commons-dbcp2</artifactId>
@@ -248,7 +271,7 @@
 			<artifactId>jbcrypt</artifactId>
 			<version>0.4</version>
 		</dependency>
-		
+
 		<dependency>
 			<groupId>de.ids_mannheim.korap</groupId>
 			<artifactId>Krill</artifactId>
@@ -258,14 +281,18 @@
 					<groupId>org.xerial</groupId>
 					<artifactId>sqlite-jdbc</artifactId>
 				</exclusion>
-				<exclusion> 
-			        <groupId>org.slf4j</groupId>
-			        <artifactId>slf4j-log4j12</artifactId>
-			    </exclusion>
-			    <exclusion> 
-			        <groupId>org.apache.logging.log4j</groupId>
-			        <artifactId>log4j-slf4j-impl</artifactId>
-			    </exclusion>
+				<exclusion>
+					<groupId>org.slf4j</groupId>
+					<artifactId>slf4j-log4j12</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>org.apache.logging.log4j</groupId>
+					<artifactId>log4j-slf4j-impl</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>org.slf4j</groupId>
+					<artifactId>jul-to-slf4j</artifactId>
+				</exclusion>
 			</exclusions>
 		</dependency>
 		<dependency>
@@ -334,7 +361,7 @@
 			<artifactId>commons-collections</artifactId>
 			<version>3.2.2</version>
 		</dependency>
-		
+
 		<!-- jetty -->
 		<dependency>
 			<groupId>org.eclipse.jetty</groupId>
@@ -351,7 +378,7 @@
 			<artifactId>jetty-webapp</artifactId>
 			<version>${jetty.version}</version>
 		</dependency>
-		
+
 		<dependency>
 			<groupId>asm</groupId>
 			<artifactId>asm</artifactId>