Prepare 2.2.0

Author: gampleman

elm.json

@@ -3,7 +3,7 @@
     "name": "elmcraft/core-extra",
     "summary": "Utility functions for an improved experience with elm/core",
     "license": "BSD-3-Clause",
-    "version": "2.1.0",
+    "version": "2.2.0",
     "exposed-modules": [
         "Array.Extra",
         "Basics.Extra",