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Added new toolbox component for starting Neo4j server in integration tests.

- Introduces TestServerBuilder, which is meant to replace the public
  ServerBuilder API.
Make the change trackers in NodeManager thread-safe
Merge pull request #3327 from chrisvest/1.9-disable-omit-stacktrace

Disable the OmitStackTraceInFastThrow JVM feature
Always interrupt page faulters on PageCache.close

Fixes a bug where threads stuck in grabFreePage, blocked waiting for new pages
to be freed, could get stuck there if the page cache was concurrently closed
_and_ the eviction thread was in the middle of evicting pages.
Favor off-heap over on-heap LongArrays

to reduce unnecessary strain on GC, since these arrays often come in great
sizes.
Doesn't write page in batching page cache if there are no changes
Less garbage around encoding/decoding labels for nodes
Generic store processing steps in batch immporter
Ability to release memory at will in the batch importer

by making sure that only the ParallelBatchImporter holds references to the
high-volume cache objects and so can release them by setting to null.
Batch importer stages added for populating count store
CSV input integration test verifies counts after import
Also tracks ANY counts in ParallelBatchImporter
Exposes static method for reading high id from id file
Extended StoreFile#move into #fileOperation with either COPY or MOVE
StoreMigrator can tell batch importer things about the legacy store

High token ids which are essential for some calculations inside the batch importer
to know those high ids up front.
Also the last committed transaction id, so that the counts store is marked
with that id when writing it.
Fixes a label cache issue where high label id was 0

Also made LongArray#setAll more convenient to use by returning itself.
Remove the duplicate-property check from the normal execution path.
Removed some more unused code.
Merge pull request #3244 from jakewins/2.1-servertest

Added new toolbox component for starting Neo4j server in integration tests