Union keys when passing array to except
Union keys when passing array to except

Instead of intersecting keys - union them when doing
`set.except(filters)`.

When doing `Model.all.except(key: %w{some ids})`
it more sense to return (all - (some + ids))
instead of (all - (some & ids)).

universsky/ohm,xxuejie/sohm,lanastasov/ohm,soveran/ohm