Swap out moment for date-fns

[razzius]

PROOF that the date functionality still works (time from now is displayed in projects list):

The other use case is formatting a date:

> new moment().format('MMM Do [at] h:mm A')
'Jul 11th at 7:43 PM'
> format(new Date(), 'MMM Do [at] h:mm A')
'Jul 11th at 7:43 PM'

[razzius]

The bundle sizes are actually a regression, probably because chrono-node (a natural language date parser) depends on moment.

Stats from env PROFILE_BUILD=true npm run preview http://localhost:3000/profile/webpack-visualizer.html:

Before: Stat 11.09 MB Parsed 4.91 MB Gzipped 1.3 MB

After: Stat 11.49 MB Parsed 5.09 MB Gzipped 1.33 MB

[razzius]

The date parsing is occurring in AssignmentCreatorForm.jsx

I've never used the AssignmentCreator functionality. Just to make sure, can anybody comment on how it's part of the app, maybe with a helpful screenshot?

[razzius]

If we removed chrono-node, the bundle is as expected significantly smaller.

Stat 10.81 MB Parsed 4.74 MB Gzipped 1.25 MB

[paulproteus]

I see that chrono-node now depends on dayjs as its one dependency. https://github.com/wanasit/chrono/blob/master/package.json#L49 Perhaps someone else coming by this PR will find an interest in checking the size impact of upgrading chrono as well as migrating popcode itself to dayjs.

This PR as-is could be a good approach, too!