Update pom to java 1.6

Author: tdebatty

Diff for: pom.xml

@@ -112,8 +112,8 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.6.1</version>
                 <configuration>
-                    <source>1.5</source>
-                    <target>1.5</target>
+                    <source>6</source>
+                    <target>1.6</target>
                 </configuration>
             </plugin>