Add the packaging metadata to build the node snap

[come-maiz]

This package will let you publish the latest nodejs in the Ubuntu store, and from there reach many users on all the supported Ubuntu versions, and more Linux distributions in progress. You just have to go to https://build.snapcraft.io and enable the automated continuous delivery.

[develar]

This project uses electron-forge and so, any target of electron-builder can be used (snap options). So, this metadata is not required (and not correct, electron-builder contains correct set of required packages for Electron app), electron-builder generates it for you.

Need to add electron-forge-maker-snap to build snap.

[come-maiz]

Hey @develar, this is not for the installer GUI, but for node itself.