v7.8.1-rc.1: bug fixed for null object hash value and string storage in object int…

…ern pool

HistoricalStateCreator refactor and ObjectDataElements split/join utiilities

HollowObjectTypeDataElements utilities for splitting and joining (#642)

* HollowObjectTypeDataElements utilities for splitting and joining

* Assume non-uniform field width across shards, add tests for filtered fields

* Restore private modifier, cleanup, more test

* Work in tandem with isSkipTypeShardUpdateWithNoAdditions

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Co-authored-by: Sunjeet Singh <sunjeets@netflix.com>

HistoricStateCreator refactor for resharding

Assume non-uniform field width across shards, add tests for filtered …

…fields

HollowHistoryKeyIndex improvements to build index faster

v7.6.5

Switched from linear probing to chaining

v7.6.4

• Expose InMemoryBlobStore as test utility under hollow-test
• recordFieldAccess introduces a non-neglible delay in field access for…

v7.6.3

VarInt helpers, Perf api generation tweak, delta cleanup tweak

v7.8.0-rc.1

Test passing MDC context(like namespace) from upstream and clearing it.

v7.6.3-rc.5

Merge change from steven

v7.6.3-rc.4

Merging changes from steven in https://github.com/Netflix/hollow/pull…

…/624

v7.6.3-rc.3

Merging changes from steven in https://github.com/Netflix/hollow/pull…

…/624