e-cli-ts has same addon ordering constraints as blueprints

Author: mike-north

package.json

@@ -107,6 +107,11 @@
     "configPath": "tests/dummy/config",
     "before": [
       "ember-cli-babel"
+    ],
+    "after": [
+      "ember-source",
+      "ember-data",
+      "ember-decorators"
     ]
   },
   "prettier": {

ts/addon.js

@@ -29,7 +29,7 @@ module.exports = {
     // dependency on install.
     if (this.project.addons.includes(this)) {
       this.project.addons.splice(
-        this.project.addons.map(a => a.name).indexOf('ember-source') + 1,
+        this.project.addons.map(a => a.name).indexOf('ember-cli-typescript') + 1,
         0,
         this.addons.find(addon => addon.name === 'ember-cli-typescript-blueprints'));
     }