Feature suggestion: default window

[orbitbot]

Given that drag'n'drop functionality for markdown files exist (#69), would it be feasible to have a default view for the app when started in a folder without an existing .md file?

Eg. something like this (just a single UX element without animations or simple text would work fine)
https://cdn.css-tricks.com/wp-content/uploads/2015/11/drag-drop-upload-1.gif

I'd be willing to work on a PR for this if you're interested, but am swamped with things at least the upcoming week, so if someone else is keen just go ahead.

[maxkueng]

This is a cool idea!

[matthewdias]

I think this is a good candidate to go along with #25. If it was packaged as an app that could be opened standalone, and also had a file handler, I think it'd be alot more useful. (Packaging also means your terminal window doesn't get hijacked).