fixed NMS-6478: bad info node up/node down transaction

Created a couple of events sent by poller when an outage is created
or resolved. Those events are properly managed by rtc

Conflicts:
	features/events/api/src/main/java/org/opennms/netmgt/events/api/EventConstants.java
	opennms-services/src/main/java/org/opennms/netmgt/rtc/DataManager.java
	opennms-services/src/main/java/org/opennms/netmgt/rtc/DataUpdater.java
Revert "fixed NMS-6478: bad info node up/node down transaction"

This reverts commit 8f08d07a64848bde36f65512d43b1665666f9807.
[bamboo] Automated branch merge (from 1.12:45f7389e96b5a50be969886adf9e07bf926a2523)
Revert "Include some documentation and pointers for the CORS filter."

This reverts commit b65e33cb7cc69802a6871a73e53c745f14fe5324.