Make keyboard shortcuts discoverable

[jouderianjr]

I'm sure this is not that important but would be nice if Ellie has a shortcut for the main actions like compile, save and etc. In my opinion, mainly the compile action one.

[tbash]

It does! But it's not exactly discoverable... I plan on adding UI for this but not quite sure what it should look like yet... Here's a reference to checkout: https://github.com/ellie-app/ellie/blob/master/assets/src/Pages/Editor/Effects.elm#L360