deepdanbooru projects path error handling

[yjunej]

os.makedirs(deepdanbooru_projects_path, exist_ok=True)
for path in os.scandir(deepdanbooru_projects_path):

This commit addresses the issue of a non-existent deepdanbooru_projects_path attribute in the shared.cmd_opts object.

[picobyte]

same, fixed in my branch