askopendirnames -->make files sorted by last modified by default

[rstudiocode]

There is no argument for this function to indicate if i want to sort elements by name or by modified by.
That's a bit strange as the function sort file by name alleready exists. It would be intresting to implement it in a next version.
To solve my problem i modified the filebrowser.py file by adding the following line to sereval functions self._sort_by_date(True)

filebrowser.py Here is my version for those who want to sort by modified until a version is published.

[jwansek]

This is a sensible feature request I can look into adding.

I recently fixed the "by name" sorting to be case insensitive, which most people probably want.