EM 12c, EM 13c: delete agent and targets using emcli

### Source OMS environment
 oracle@omshost[emrep]$ . oraenv <<< oms
 ORACLE_SID = [emrep] ? The Oracle base for ORACLE_HOME=/u01/app/product/em12.1.0.3_middleware/oms is /home/oracle/app/oracle
 
 ### Login to OMS as sysman user
 oracle@omshost[oms]$ emcli login -username=sysman
 Enter password : 
 
 Login successful
 
 ### Sync OMS
 oracle@omshost[oms]$ emcli sync
 Synchronized successfully
 
 ### Find monitored targets for host (myhost1)
 oracle@omshost[oms]$ emcli get_targets -format=name:csv|grep myhost1
 5,Under Blackout,oracle_database,myhost1
 6,Status Pending,oracle_dbsys,myhost1_sys
 
 ### Delete monitored target: oracle_database
 oracle@omshost[oms]$ emcli delete_target -name="myhost1" -type="oracle_database" -delete_monitored_targets -async
 Target "myhost1:oracle_database" deleted successfully
 
 ### Delete monitored target: oracle_dbsys
 oracle@omshost[oms]$ emcli delete_target -name="myhost1_sys" -type="oracle_dbsys" -delete_monitored_targets -async
 Target "myhost1_sys:oracle_dbsys" deleted successfully
 
 ### Verify monitored targets have been deleted.
 oracle@omshost[oms]$ emcli get_targets -format=name:csv|grep myhost