fix(package): update ember-cli-htmlbars to version 4.1.0

Closes #10

Author: greenkeeper[bot]

package.json

@@ -21,7 +21,7 @@
   },
   "dependencies": {
     "ember-cli-babel": "^6.6.0",
-    "ember-cli-htmlbars": "^2.0.1"
+    "ember-cli-htmlbars": "^4.1.0"
   },
   "devDependencies": {
     "broccoli-asset-rev": "^2.4.5",