Display configurable products' variation attributes in the Product List

Scenario:

• A configurable product's variations are based on a custom attribute of the type "Drop Down" called "voltage".
• A Product List element is set up to use the "voltage" attribute for one of the Attribute Columns.
• When this configurable product is displayed in the Product List, the "Voltage" column is blank because the configurable product itself doesn't have (and isn't allowed to have) a "voltage" attribute of its own (since that attribute is what the configurable product variations are based on).

Desired Feature:

For configurable products, the Product List's "Voltage" column could populate with the configurable product's variations' "voltage" attribute values in a comma-separated string. For example, if "12V", "24V", and "48V" are the three "voltage" attribute values the configurable product's variations are based on, then the "Voltage" column in the Product List would read "12V, 24V, 48V" for the configurable product.

This would allow people to see that clicking into the configurable product will give them options to select from multiple voltages.