create map of outages in Outages for performance
cleaning up Ouages, and adding a performance test

With the changes, the test for outage verification takes 2 ms. The
same test executed without the changes takes 36 ms.
Merge remote-tracking branch 'origin/1.10' into 1.12

Conflicts:
	opennms-config/src/main/java/org/opennms/netmgt/config/poller/Outages.java
	opennms-services/src/main/java/org/opennms/netmgt/config/PollOutagesConfigManager.java
	opennms-services/src/test/java/org/opennms/netmgt/config/PollOutagesConfigManagerTest.java