Catfish 4.16.3: allow GUI to run as catfish --iso-time

Hi, thanks for Catfish.

The Gui of catfish does not display the search results in iso-time format, under preferences menu it is not possible to set search result in iso format.

However, it is possible to have this feature simply by running in terminal: catfish --iso-time

Desired feature: add in preferences menu a checkbox entry which would be name as for instance "iso date format display".

It is missing GUI preferences feature of already coded feature.

In case you would need help for GUI translation, just ask.