Swap Ch9 Canvas with Ch12 Async (#250)

* Swap Ch9 Canvas with Ch12 Async

* Fix Ch9 CI - missing data-out dir

Note that a file must exist in data-out for it to be tracked by git.
The traditional strategy of adding a .gitignore file in the empty
directory is incompatible with the naive test reset strategy of
removing the entire directory. So next best option is to just populate
it with one of the expected output files.

* Update chapter name in package.json

Author: milesfrain

exercises/chapter12/.gitignore

@@ -8,4 +8,3 @@
 /.purs*
 /.psa*
 /.spago
-/test/data-out/*

exercises/chapter9/html/index.html renamed to exercises/chapter12/html/index.html

@@ -2,19 +2,20 @@
 Welcome to a Spago project!
 You can edit this file as you like.
 -}
-{ name = "my-project"
+{ name =
+    "my-project"
 , dependencies =
-  [ "aff"
-  , "affjax"
-  , "console"
-  , "effect"
-  , "functions"
-  , "node-fs-aff"
-  , "parallel"
-  , "psci-support"
-  , "strings"
-  , "test-unit"
-  ]
-, packages = ./packages.dhall
-, sources = [ "src/**/*.purs", "test/**/*.purs" ]
+    [ "arrays"
+    , "canvas"
+    , "console"
+    , "lists"
+    , "psci-support"
+    , "random"
+    , "refs"
+    , "web-dom"
+    ]
+, packages =
+    ./packages.dhall
+, sources =
+    [ "src/**/*.purs", "test/**/*.purs" ]
 }