chore(LoopBack): Upgrade to LoopBack 3

[raisedadead]

This upgrades LoopBack to v3.x.x

• Update LoopBack version
• Update use of REST error handler
• Replace LoopBack middleware “getter” properties
• Update models
• Update models derived from PersistedModel
• Explicitly add User model properties that were removed
• Remove use of current-context methods, middleware, and configuration settings
  • This throws an error, please see the linked gist below for details.
• Check request parameter encoding
• Update use of promises
• Check CORS configuration

More details of the checklist with some error stack are available here:
https://gist.github.com/raisedadead/22f7a38bb47204fded9b0877fde954ef

Closes #12780

[camperbot]

@raisedadead updated the pull request.

[camperbot]

@raisedadead updated the pull request.

[camperbot]

@raisedadead updated the pull request.

[camperbot]

@raisedadead updated the pull request.

[systimotic]

@raisedadead Is this still blocked?

[raisedadead]

Hi @systimotic I was away for a bit, I could still continue, but looks like this is closed. I'll let @BerkeleyTrue confirm if there are other plans before I continue.

Cheers.

[systimotic]

@raisedadead 👍 No worries. I'm pretty sure this was closed as stale, as a part of the massive cleanup. If you want to update this / get it reviewed, I think you're free to reopen it.

[raisedadead]

Sure, I just got whats going on... lol. Thanks for the link. I'll make a fresh pull request (I have to update the code anyways) because we need this upgrade

[systimotic]

@raisedadead Awesome!