File dialog filters

[Christian Dávid]

Hi,

the latest review request 127057 made me think about using something like

QMimeDatabase db;
db.mimeTypeForName("application/x-gnucash").filterString()

to create the filters. Then we do not need to manage the file extensions anymore 
and the translators have less work to do (the filterString is localized 
already). Also the translations are consistent in all apps.

What do you think? Is there a KDE policy about that?

Greetings
Christian

[RR 127057] https://git.reviewboard.kde.org/r/127057/