Add initial Scratch testing steps (#305)

* Add initial Scratch testing steps

* Update testing.md

Author: vorburger

docs/testing.md

@@ -9,10 +9,24 @@
 
 ## Scratch 3.0
 
+First test that Eric's (!) saved project (which is in git) works:
+
 1. Right click the "Piggy" and verify it say "Hello, my friend!"
 1. type `/scratch_test` verify the title shown
-1. `/make` and open the browser
-1. _TODO_
+
+Now test that Michael can make a new project:
+
+1. `/make` and click the link in the Minecraft Chat to open the Scratch UI in the browser
+1. Add
+   * when / `demo`
+   * `Piggy` speaks `I like Scratch`
+1. `/demo` should work
+1. click _Save_
+1. close Browser
+1. _TODO `/demo` should still work, but currently doesn't anymore (because project JSON wasn't automagically moved from `/minecraft-server-test-data/config/storeys-web/working/` to `storeys-web/scratch/`)_
+1. `/make` again
+1. Verify that previously created blocks still appear
+1. _TODO `/demo` should still work, but currently doesn't, because of `IllegalArgumentException: A plugin may not register multiple commands for the same alias ('demo')` in log; this needs more thoughts in general._
 
 ## JavaScript