remind user to upgrade packages

[EricWVGG]

I think it'd be really neat if gatsby develop would remember the last time a user ran package updates (I use yarn upgrade-interactive --latest) and periodically reminded the user, "30 days since you last updated Gatsby" or whatever.

[AnilSeervi]

Change the develop command in package.json to be

yarn upgrade-interactive --latest && gatsby develop

this way it'll check everytime you run yarn develop

[EricWVGG]

Well that sounds just awful, but upon further reflection this idea is outside the demesne of Gatsby, so I'll just retract this.