data_dir not used by flighpath save

[Reimar Bauer]

We have introduced data_dir parameter by 1.7.0.

Somehow not all of our store/load methods use it as initial path

This needs a review.

[Reimar Bauer]

elif pickertype in ["qt", "default"]:
     filename = get_open_filename_qt(parent, title, dirname, filt)

looks like did not understand dirname

[Reimar Bauer]

data_dir becomes used by the qt filepicker too, fixes #337

→ <<cset ee5916d83325>>

[Reimar Bauer]

Merged in ReimarBauer/mss/stable (pull request #557)

data_dir becomes used by the qt filepicker too, fixes #337

→ <<cset 254ffcfd34b1>>