TEZ-931. DAGHistoryEvent should not be allowed to be sent to Dispatcher/EventHandlers. (hitesh)
TEZ-930. Provide additional aggregated task stats at the vertex level. (hitesh)
TEZ-930. Addendum patch. Provide additional aggregated task stats at the vertex level. (hitesh)
TEZ-935. Fix function names for Vertex Stats. (hitesh)
TEZ-933. Change Vertex.getNumTasks to return the initially configured
number of tasks if initialization has not completed. (sseth)
depending on when it's called. (sseth)