File picker does not remember sort preferences.

[XV-02]

When opening a file in cosmic-edit (fb151fd), the file picker will always sort by the name field, which displays results first by a folders-then-files hierarchy and then by alphabetical sort. This is true, even if the last time the file-picker was interacted with, the user sorted by another value.

Generally, I would expect users to interact with their files in fairly consistent ways. As such it feels like the user's last preference for sorting should be maintained when the file-picker is next instanced.

Remembering the preferred sort appears to be the behaviour in gedit and Kate.

I would note that even when sorting by last-modified, gedit and Kate both present results in a folders-then-files hierarchy before applying the sorting criteria. Currently, cosmic-edit only lists items by the sort-criteria except when sorting by name.