Added ReloadingDetectorFactory interface.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/configuration/trunk@1461169 13f79535-47bb-0310-9956-ffa450edef68
Added a property for a ReloadingDetectorFactory to FileBasedBuilderParametersImpl.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/configuration/trunk@1461170 13f79535-47bb-0310-9956-ffa450edef68