Add 'yarn rw upgrade' helper to upgrade @redwoodjs packages

[thedavidprice]

Step 1 of #271

• yarn rw upgrade runs an interactive upgrade process
• yarn rw upgrade --check checks for outdated packages (without upgrading)

Experimented with npm-check-updates, npm-check, and yarn-check. Ended up using yarn built-in checks and upgrade. However, yarn doesn't play nice with its own workspaces, go figure, so I was limited to use yarn upgrade-interactive [packages] --latest. Other commands/options would not work. 👎

I also attempted to first build this without Listr, but Execa didn't play nice with the interactive terminal. So Listr it is (I seem to recall we've had this problem before, yes?).

Note the .strict() in the option -- it does pick up error in the "check" flag, which is an improvement on no error checking at all.

Tested on Windows Bash for Ubuntu and worked fine. Wasn't able to figure out how to test cli package on Powershell... ?

[peterp]

This is awesome, does this modify all 3 the package.json files as well as the yarn.lock?

[thedavidprice]

@peterp Yes, it does both 1) modify respective package.json files and 2) install and, therefore, update yarn.lock. You can try with yarn:

• yarn upgrade-interactive [package-name] —latest
• yarn outdated [package-name | defaults to checks all]

The interactive cli is nice but a bit more complicated. It will especially be a benefit in the future when people are way behind and will receive visual understanding about how many, and which, patch/minor/major versions they would be skipping to upgrade to latest. —> Downside of the yarn workspace bug (with its own command) is that we can only use this for upgrading to latest. I think this is satisfactory for now.

[peterp]

Yay!