ISPN-3417 Threads which get parked in CHMv8 won't ever be unparked
ISPN-3405 Cache stores hashing keys should use configured Equivalence

* Removed Bucket externalizer since it complicated injection of
per-cache equivalence function.
* Created EquivalentLinkedHashMap for the single file cache store
to be able to locate keys requiring Equivalence function in memory.