Reingest: Update parse to DB

refs #6488

Handle files with formats not found in the local FPR. Only parse DC
metadata associated with the SIP as a whole, not a single file. Do not
parse rights identifiers, since they are not common. Give default empty
string values to all rights fields, since they may be empty.
METS: Refactor create METS rights

Pull creating a single rightsStatement into its own function for use in
reingest. Clean up duplicate code and DB queries so only common fields are
required and everything else is fetched and used as needed.
Reingest: Update METS for rights

refs #6495

Add PREMIS Rights to reingest METS. New rightsMDs are added, but superseded
rightsMDs are not marked.
Reingest: minor fixes

Pass SIP directory instead of METS path to update_mets. root is modified in
place, do not return it.
Reingest: Add new metadata files

refs #6495

Add new metadata files to the METS; add amdSecs, update structMap and
fileSec.
Reingest: Handle marking superseded rights

refs #6495