[EAGLE-1024] Monitor jobs with high RPC throughput https://issues.apache.org/jira/browse/EAGLE-1024 * add job RPC data in MAP_REDUCE_JOB_STREAM * refactor org.apache.eagle.jpm.analyzer.publisher.EmailPublisher * support new config 'application.analyzerReport.alertLevel' to define alert level Author: Zhao, Qingwen <qingwzhao@apache.org> Closes #938 from qingwen220/EAGLE-1024.