Initial commit of a CompositeTriggeringPolicy and associated test. Allows multiple triggering policies to be 'or'd together to determine if an event should trigger rolling. CompositeTriggeringPolicy can be configured via xml configuration by adding child 'triggeringPolicy' nodes to the CompositeTriggeringPolicy. Did not change the DTD.
logging/log4j/companions/extras/trunk/src/main/java/org/apache/log4j/rolling/CompositeTriggeringPolicy.java