Trim {Lower,Upper}Bound for table iteration

Question

NB: this change is in anticipation of pushing lower/upper bound checks down into sstable.Reader.

Trim IterOptions.{Lower,Upper}Bound when loading a table to avoid requiring lower/upper bounds checks if all of the keys within the table pass the checks.

See #28

该提问来源于开源项目：cockroachdb/pebble

Answer 1

This change is