This version is likely the last version of 5.1.  5.2 migration tested against 20+ different backup systems and working well.

More work on migration to 5.2

• handle deposits incorrectly logged on spares invoices moving parts onto workshop/units/deals
• handle historically mismatched AP/AR txns where posted journal's status is mismatched.
• cope with historically invalid deposits, such as deal deposits incorrectly parked on an invoice
• assume reclaim_total for spares deposits is authoritative, not merely materialized tally of deposit_reclaims and bend general ledger around this.