Make OtherThreadExecutor implement Closeable to make orderly thread
shutdown easier.

o Callers can now use try-with-resources.
Make NestedTransactionLocksIT more readable.
Ensure that all tests close transactions reliably.

o Recent changes to database shutdown mean that we now wait for transactions
   to finish when shutting down. This mean that each of the many tests which did
   not close their transactions was hanging for 20 seconds before failing.
Added more information about the refnode deprecation. Point to the correct live console server.
Revert "Revert "Added additional HA logging.""

This reverts commit 9950dc2c92ab7fa71b3be32026fb37f56cd64e08.
Resolve incorrectly merged paxos lifecycle management.

o Re-introduce the paxoslife that was removed as part of the merge conflicts.
o Resolves a race condition in which the cluster would hang during switch to slave in
  some alignments of stars.
Fixed the linked list example queries. Moved it to the graphgist format.
Merge pull request #1474 from jakewins/merge-unclosed-txns

Fix unclosed transactions in tests, re-enable proper shutdown cycle.
Revert "Revert "Revert "Added additional HA logging."""

This reverts commit 8ce073949bb425fb1120b3c308f18caa871d8139.
Change locking of nodeGetUniqueFromIndexLookup

o Now guaranteed to hold a read lock if a node is existing or a write lock if no node was found
o Use a fresh index reader to see concurrent changes
o This commit fixes some code analysis warnings
o Ensure InMemoryIndex does not apply updates idempotently when not used as unique index
o Make sure that we work with index descriptors correctly w.r.t. schema
o Take schema read lock
o Use forceGetRecord when using loading schema rules
o Do not verify if a constraint index is online from Cypher
   (they always are and if not due to failure that is detected by kernel)
o Add embedded example on how to use Cypher to create unique nodes to manual