Option to overwrite instead of append output

[AtHeartEngineer]

Adding the ability to overwrite instead of append output as an option would be really useful. Especially if you could do it per output type. Like I don't want the text format to keep appending, because then it just becomes a really long file that isn't useful except for the end. But if the json file could keep appending, that would be great, because then I could make charts out of it.