change java version to 1.6

- This should solve the Override-Annotation error

mustang/pom.xml

@@ -27,16 +27,16 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-compiler-plugin</artifactId>
-        <version>2.3.2</version>
+				<version>3.2</version>
 				<configuration>
-          <source>1.5</source>
-          <target>1.5</target>
+					<source>1.6</source>
+					<target>1.6</target>
 				</configuration>
 			</plugin>
 		</plugins>
 	</build>
-  <dependencies>
 
+	<dependencies>
 		<dependency>
 			<groupId>org.apache.pdfbox</groupId>
 			<artifactId>pdfbox</artifactId>