Merge branch '1.9-maint' into 2.0-merge-1.9

Conflicts:
	community/kernel/src/main/java/org/neo4j/kernel/IndexManagerImpl.java
	community/kernel/src/main/java/org/neo4j/kernel/impl/storemigration/StoreMigrator.java
	community/kernel/src/main/java/org/neo4j/kernel/impl/storemigration/legacystore/LegacyStore.java
	community/kernel/src/test/java/org/neo4j/kernel/impl/storemigration/StoreMigratorTestIT.java
	enterprise/cluster/src/main/java/org/neo4j/cluster/protocol/atomicbroadcast/multipaxos/LearnerContext.java
	enterprise/cluster/src/main/java/org/neo4j/cluster/protocol/atomicbroadcast/multipaxos/LearnerState.java
	enterprise/cluster/src/main/java/org/neo4j/cluster/protocol/atomicbroadcast/multipaxos/MultiPaxosContext.java
	enterprise/cluster/src/main/java/org/neo4j/cluster/protocol/heartbeat/HeartbeatState.java
	enterprise/cluster/src/test/java/org/neo4j/cluster/protocol/atomicbroadcast/multipaxos/ProposerStateTest.java
	enterprise/cluster/src/test/java/org/neo4j/cluster/protocol/heartbeat/HeartbeatContextTest.java
	enterprise/cluster/src/test/java/org/neo4j/cluster/protocol/heartbeat/HeartbeatStateTest.java
	enterprise/ha/src/main/java/org/neo4j/kernel/ha/cluster/zoo/ZooKeeperHighAvailabilityEvents.java
	enterprise/ha/src/test/java/org/neo4j/ha/QuorumWritesIT.java
	enterprise/ha/src/test/java/org/neo4j/ha/TestPullUpdatesApplied.java