Upgrade to Maven Dependency plugin 2.9

Release Notes - Maven Dependency Plugin - Version 2.9



** Bug
    * [MDEP-424] - Maven Dependency Plugin homepage should link to dependency:list-repositories
    * [MDEP-439] - maven-dependency-plugin not compatible with Java 8
    * [MDEP-445] - dependency plugin fails with >9 threads
    * [MDEP-448] - NullPointerException when classifier sources was chosen



** Improvement
    * [MDEP-443] - dependency tree should be the same when using verbose or not
    * [MDEP-450] - Add goal display-ancestors which will output the line of heritage for parent poms
    * [MDEP-457] - Enhanced documentation for includeArtifactIds and includeGroupIds
    * [MDEP-459] - Update maven-dependency-analyzer to 1.5
    * [MDEP-460] - Removed dependency plexus-container-default:1.0-alpha-9-stable-1
    * [MDEP-461] - Upgrade plexus-archiver to 2.4.4
    * [MDEP-462] - Upgrade to Maven Dependency Tree version 2.3
    * [MDEP-463] - Fix RAT Report
    * [MDEP-464] - Upgrade maven-invoker 2.0.11 to 2.1.1

** New Feature
    * [MDEP-427] - Add user property for addParentPoms option


** Task
    * [MDEP-227] - Bump to Doxia 1.1.1
    * [MDEP-452] - Use mock repository manager for ITs
    * [MDEP-453] - Change Maven prerequisite to 2.2.1