Continuing from szwacz/electron-boilerplate#172

Afaik on npm run dist electron-builder drops everything from the output-Directory. It then fetches the latest artifact from upstream and builds the delta etc.

I'd like electron-builder to not delete any files. It may overwrite an existing previous version with the downloaded one but imho it shouldn't delete other files in the directory.

For what do you need old artifacts?

I keep backups of every version. If an user experiences some problems I can always verify the issue with the exact version of the application. Clearly the output-directory isn't the place to keep backups long-term. But anyway, I tend to forget to always backup the build right after building it. After another npm run dist it's gone :(

Also, is it stated in the docs that the contents of the output-dir are discarded on every build? I was surprised and puzzled the first time I experienced it. It's a huge pita if you have some other files put there (e. g. a readme). If it's not in the docs please add it. (Gotta hurry to catch the train now, sorry.)

Thanks for your efforts :)