exposure setting fails because of locale

[fphg]

Seems that parsing of values with decimals (0.1, 0.001) fails when the system's locale uses comma as decimal separator.

Symptom is : exposure values below second render black frames (0 or minimal exposure).

Workaround :

export LANG=en_US.utf-8;
export LC_ALL=en_US.utf-8;
./gtk3Imager

[OpenSkyProject]

It's fixed on 0.6.1 when picking values from the list. Yet no user input management, hence please be sure to use the correct decimal separator according to your locale.
This will be fixed too, but at a later stage.