OPENDJ-1308 (CR-3156) Migrate schema support - ByteString - Indexer
Used ByteString everywhere with the JE Backend Indexer.
Changed all code up down and sideways to use ByteStrings too.
AttributeIndex.java:
Added BSKeyComparator to match the order defined by KeyComparator for backward compatibility.
Index.java:
Added byte string comparator field.
Indexer.java:
Pulled up comparator field + getComparator() here.
Added bsComparator field + getBSComparator() for ByteStrings.
VerifyJob.java:
In verifyAttribute(), reused the DatabaseEntry object.