Don't ask for directory

[vojto]

In 99% cases you want to save unretined files to the same directory. Asking for directory each time is very annoying.

Here's my fix if anybody would find this useful: vojto@ba6838b

I'm not making a pull request since I basically removed a feature, I just wanted to let people know about my version.

[beny]

So you can make option in Preferences for that and make pull request