feat(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
• Check request parameter encoding
• Update use of promises
• Check CORS configuration

More details of the checklist:
https://gist.github.com/raisedadead/22f7a38bb47204fded9b0877fde954ef

Closes #12780

[fizzvr]

Why blocked? seems nice to upgrade the project, idk

[raisedadead]

Why blocked? seems nice to upgrade the project, idk

It's a WIP actually but is blocked because some of other PR's especially those touching the models will have to land before this goes in.

Please feel free to pull down and test though.

[camperbot]

@raisedadead updated the pull request.

[camperbot]

@raisedadead updated the pull request.

[raisedadead]

I think this is ready for a QA. I have three items on the checklist that I am confident that I have done a review of, but unsure and would love a second set of eyes.

[BerkeleyTrue]

Thanks for the PR. How much QA will this need. It seems to simple to be the only required changes.

[raisedadead]

Honestly, this adds only the most minimum of changes needed to move to LB3, thanks to the fact that we do not use much of the features of Loopback.

You have already fixed a ton of issues with the error handling and the promise handling by customising it.

To, my best knowledge we should be safe, by merging this.
This is better than having the 2.x which is having tons of unhandled issues and isn't receiving any upgrades in a long time.

My advise though is to schedule this one of the incremental candidates in the RC plan, and roll back just one this if you do see issues, which I am hoping that you might not have to.

[BerkeleyTrue]

The code looks good as far as I can see. Since loopback touches so many things I don't want to leave this till RC. I'm completely frustrated with loopbacks 2.0 LTS not fixing anything. I'll merge this in and update beta.

[raisedadead]

Sure, thanks!

[BerkeleyTrue]

May have spoke to soon. I'm getting cannot find adler32 when trying to run node seed. Doesn't seem like the package lock file is complete. I'lll remedy this shortly
nvm, my mistake. I forgot to explicitly install the dev packages