Electron app signing

[carlosperate]

There are currently two main ways to package electron apps:

• Electron Forge
• Electron Builder

They both seem to offer very very similar functionality, and the last time I did some research to pick an option Electron Builder seemed to offer an easier path to app signing (and more articles and tutorials covering it), it also offered app auto-updating without extra servers (just GitHub releases). That was a while ago and things might have changed since then (looks like Forge now also auto-updates via GH Releases), but they are both still good options in general.

PR #13 implemented packaging with Electron Builder as that is the project I was already familiar with and it offers and simple and quick way to continue iterating with this project.

If we need something not offered by Electron Builder, changing to other options (like Forge) hopefully shoudn't be too problematic. So, @ntoll I would recommend to have a look at the app signing docs (Forge, Builder), in case something jumps at you at being easier or more difficult than the other.