[REF] extract loadSavedMapping

[eileenmcnaughton]

Overview

This is a very 'untouched' extraction so that it can be reviewed / replicated easily. Ideally more follow up will be in subsequent PRs (now or down the track)

Before

One long function

After

One IF's worth in it's own function

Technical Details

Ideally we would use the same functions as the export does now we have improved functions for this stuff & no-one will ever have to make sense of this stuff again.

Comments

[civibot]

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