system properties should always override file config

git-svn-id: https://svn.apache.org/repos/asf/tomee/tomee/trunk@1458874 13f79535-47bb-0310-9956-ffa450edef68
sxc is released

git-svn-id: https://svn.apache.org/repos/asf/tomee/tomee/trunk@1458876 13f79535-47bb-0310-9956-ffa450edef68