Bug 16251: Fix value of material select for Rancor 008 widget

Bug 16251: Fix value of material select for Rancor 008 widget

The material type is selected in accordance with the leader (06-07)

Test plan:
1. Create a new record using the advanced editor
2. Set the leader 6th position to 'c'
3. Save the record and reload the page
4. 'Music' should be automatically selected for 008
5. Try other values for the leader 6th and 7th positions

See comment 0 of this bug for the complete mapping

Signed-off-by: Michal Denar <black23@gmail.com>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>