[MTOOLCHAINS-6] updated sample custom toolchain to be compatible with Maven 2.0.9-3.2.3 and Maven 3.2.4+: see MNG-5718 and MNG-5720

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1636790 13f79535-47bb-0310-9956-ffa450edef68