NMS-4951 send an event when node categories change in provisiond
Merge branch '1.12'

Conflicts:
	opennms-model/src/main/java/org/opennms/netmgt/model/OnmsNode.java
	opennms-provision/opennms-provisiond/src/test/java/org/opennms/netmgt/provision/service/ProvisionerTest.java