[Mediawiki-l] How do you allow zip files uploads

[DaveM]

I need to configure my wiki to allow uploading of zip files. Now I have
added it to my LocalSettings.php file. However I see that it is still
blacklisted and I need to change this setting in another file. I have done
quite a bit of reading up on this but I am still in the dark as to what file
I need to edit and what I need to edit into it?