Add options to EXCLUDE in filters

To manage our products effectively we use filters to get the right results. In the product tab its currently only possible to INCLUDE a specific 'Vendor', 'Distributor' or 'Category'. However, in certain situations it would be better to EXCLUDE these values.

Example:

I want to see all products that meet the following criteria:

1. Part number: available
2. Stock: not found
3. Vendor = not (our company)

Number 3 is currently not possible, but would be very useful