Update to 0.19

[ivanistheone]

I've installed latest elm, but I don't have elm-package on the command line.

How hard would it be to update this tutorial to latest build chain?

I went to part1/ and ran elm-upgrade and got elm make Main.elm to compile
but then elm-live Main.elm --open --output=elm.js returns:

elm-live:
  I can’t find the command elm-make!
  Looks like elm-platform isn’t installed. Make sure you’ve followed
  the steps at https://git.io/elm-platform and that you can call
  elm-make from your command line.

[DavidSSL]

From what I understand there is actually a V2 of this course https://github.com/rtfeldman/elm-0.19-workshop which uses 0.19 https://frontendmasters.com/courses/intro-elm/.

[svitebskiy]

I've made a direct port of this repo to Elm 0.19.1 in this fork: https://github.com/svitebskiy/elm-workshop.
I believe it is still relevant as some learning sites, like PluralSight, still only have the older 2018 version of this workshop, and setting up separate a working Elm 0.18 environment is a bit of a pain right now.