Add -o/--column-order option to insert and upsert

[ChrisJr404]

Closes #474

insert and upsert build their table using the order of columns in the incoming data. This adds -o/--column-order so you can say which columns should come first, the same way sqlite-utils transform -o already works:

sqlite-utils insert dogs.db dogs dogs.csv --csv -o name -o age

You can pass it more than once. Columns you don't name keep their original order after the ones you do, and it only affects tables the command creates, so an existing table's column order is left alone. Under the hood it just passes column_order through to insert_all(), which already supported it.

Added tests covering both insert and upsert, plus a short docs section.

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📚 Documentation preview 📚: https://sqlite-utils--847.org.readthedocs.build/en/847/