Upgrade to Logback 1.1.6

Closes gh-5410

spring-boot-dependencies/pom.xml

@@ -112,7 +112,7 @@
 		<liquibase.version>3.4.2</liquibase.version>
 		<log4j.version>1.2.17</log4j.version>
 		<log4j2.version>2.4.1</log4j2.version>
-		<logback.version>1.1.5</logback.version>
+		<logback.version>1.1.6</logback.version>
 		<mariadb.version>1.2.3</mariadb.version>
 		<mockito.version>1.10.19</mockito.version>
 		<mongodb.version>2.13.3</mongodb.version>

spring-boot/src/test/java/org/springframework/boot/context/config/ConfigFileApplicationListenerTests.java

 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -106,7 +106,7 @@ public class ConfigFileApplicationListenerTests {
 		LoggerContext loggerContext = ((Logger) LoggerFactory.getLogger(getClass()))
 				.getLoggerContext();
 		loggerContext.reset();
-		BasicConfigurator.configure(loggerContext);
+		new BasicConfigurator().configure(loggerContext);
 	}
 
 	@After

spring-boot/src/test/java/org/springframework/boot/logging/logback/SpringBootJoranConfiguratorTests.java

 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,6 +25,7 @@ import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.slf4j.impl.StaticLoggerBinder;
 
 import org.springframework.boot.logging.LoggingInitializationContext;
@@ -71,7 +72,7 @@ public class SpringBootJoranConfiguratorTests {
 	@After
 	public void reset() {
 		this.context.stop();
-		BasicConfigurator.configureDefaultContext();
+		new BasicConfigurator().configure((LoggerContext) LoggerFactory.getILoggerFactory());
 	}
 
 	@Test