New File in Directory Formate leads to an issue

[moehrlich]

If you accidentaly add an new file to the Formate Directory the system does not know what it has to do with that file and did not starts correctly. It should ignore these file or should show a error message.

[EliDeh]

A error message will be added

[jsubhi]

Non-json Files are ignored now - good. But any invalid json file in the Formate directory seems to force default values on all other settings in the program. The settings in config.json and all the formats no longer apply.
This behaviour can be reproduced by adding an empty "test.json" to Formate or by adding an extra comma to default_gross.json for example.
Not a major issue but a more robust handling would be nice, e.g. quitting with "invalid configuration in test.json"

[jsubhi]

Looks good now. Thanks!