Create __init__.py

[Mte90]

Avoid this crash if the python script is executed:

Traceback (most recent call last):
  File "/home/mte90/Desktop/kde/goldwarden/gui/goldwarden_ui_main.py", line 2, in <module>
    import src.linux.main as linux_main
ModuleNotFoundError: No module named 'src.linux'

[quexten]

Hmm, when running python3 goldwarden_ui_main.py from the gui directory or python3 gui/goldwarden_ui_main.py from the goldwarden directory, I don't get this error. I'm happy to merge this, though how did you run it for the error to occur?

[Mte90]

I get that from the parent folder of the project, that files let python knows that the folder is a module folder so can load them.

[quexten]

Thanks for clarifying and for the PR.