Configure executable output directory.

[aslilac]

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Currently electron-packager is just always called on a directory named "out". It would be nice if we could control the name of this directory, preferable by just allowing us to set the "out" property for "packagerConfig".

[GrandSchtroumpf]

Is there any plan concerning this issue ? I'm working in a monorepo with several applications and would be great to be able to specify out path.

[nishant-labs]

It will be great if anyone could make this happen, really annoying while working in monorepo

[CMCDragonkai]

This will be really helpful in NixOS, we cannot mutate the input directories inside /nix/store. It's important to set the output directory.

[hadwrf]

I need to modify out directory. It should be configurable.

[jeanbmar]

PR https://github.com/electron-userland/electron-forge/pull/2714 submitted, I can't use Electron without this feature either.