[New feature] Adding filters for multiselect field of Pimcore classes.

[Yivan]

Hello,

Actually the select and multiselect filters work only with single select field of Pimcore classes.
Like the native Pimcore e-commerce, it would be great to have those two filters for the multiselect field of Pimcore classes.

Here is a screenshot of native Pimcore e-commerce framework:

As CoreShop filters use the same logic, it should be feseable.

So there will be 4 filters:

• Select for Select field => already exists
• Multiselect for Select field => already exists
• Select for Multiselect field => new one, proposed in this issue
• Multiselect for Multiselect field => new one, proposed in this issue

Original discussion was here: #841
Documentation should be updated too: #887

Thanks.

[dpfaffenbauer]

done

[Yivan]

Great news ! Thanks