Use update-during-copy-and-just-swap-tables approach to update PartTable

We create a PartTable_new with the new layout, populate
PartTypeTable, then we copy all data from PartTable to
PartTable_new and we modify the data on flight using
'INSERT INTO ... SELECT FROM ...' and then we just
rename PartTable_new to PartTable and drop the old one

This speeds up migration on MySQL by 50% as it avoids
copying the entire table twice for ALTER TABLE and also
works on SQLite