chore(package): update ember-cli-htmlbars to version 4.2.0

Closes #39

Author: greenkeeper[bot]

package.json

@@ -27,7 +27,7 @@
     "ember-cli-babel": "^7.1.2",
     "ember-cli-dependency-checker": "^3.0.0",
     "ember-cli-eslint": "^4.2.3",
-    "ember-cli-htmlbars": "^3.0.0",
+    "ember-cli-htmlbars": "^4.2.0",
     "ember-cli-htmlbars-inline-precompile": "^1.0.3",
     "ember-cli-inject-live-reload": "^1.8.2",
     "ember-cli-sri": "^2.1.1",