Investigate adding a game auto-updater

[lazerwalker]

There has to be an existing Electron module for auto-updates.

We'll need a CDN to load the updated assets from (that ideally isn't just GitHub raw files) so this may be blocked on #18 for having a deployed CDN'd version of the latest assets. That GH Pages deploy could also theoretically include a version canary file used to check for updates.

[lazerwalker]

https://www.electronjs.org/docs/latest/tutorial/updates