LP#849143 fix some gaps in bib record merging

LP#849143 fix some gaps in bib record merging

Tweaks asset.merge_record_assets such that it considers acquisition line items and user requests, serial subscriptions, booking resource types, biblio monograph parts, and biblio peer bib copy maps. I'm not handling vandelay.queued_record.imported_as or any other vandelay tables, but we may wish to do that too. We're also leaving acq.acq_lineitem_history alone.

Signed-off-by: Jason Etheridge <jason@esilibrary.com>
Signed-off-by: Mike Rylander <mrylander@gmail.com>