Fix Categories to show all existing and add them to all icons

[Kaiserdragon2]

Not Urgent

[TotallyAvailable]

Does the current implementation actually allow for an "Alternatives" category ('_alt' + '_alt_*') as mentioned in #1938 or would that require more/too much work.

[Kaiserdragon2]

Does the current implementation actually allow for an "Alternatives" category ('_alt' + '_alt_*') as mentioned in #1938 or would that require more/too much work.

At the moment we check the beginning of the filename i don't know if it is easily possible. I will have to look into that