Drop support for Node 6

Author: Turbo87

.travis.yml

@@ -3,7 +3,7 @@ language: node_js
 node_js:
   # we recommend testing addons with the same minimum supported node version as Ember CLI
   # so that your addon works for all apps
-  - "6"
+  - "8"
 
 branches:
   only:

appveyor.yml

@@ -4,7 +4,7 @@
 environment:
   MOCHA_REPORTER: "mocha-appveyor-reporter"
   matrix:
-    - nodejs_version: "6"
+    - nodejs_version: "8"
 
 branches:
   only:

package.json

@@ -26,7 +26,7 @@
     "lodash.defaultsdeep": "^4.6.0"
   },
   "engines": {
-    "node": "6.* || 8.* || >= 10.*"
+    "node": "8.* || >= 10.*"
   },
   "changelog": {
     "repo": "ember-cli/ember-cli-uglify",