A .md file uploader, that'll allow the user to edit the downloaded note

[parasmanikc]

Problem
When working with local storage, I downloaded the note in .md format, but I realized there was no way to work again on
the downloaded file, after I close the browser

Solution
A simple .md file uploader. That'll open the downloaded note in the browser, which we could edit and download again

Notes
Please let me know if this can be a good feature in this project. I've implemented something similar in my past project, and I would
love to make this contribution.