CI: test ember 2.18.2, use lts node in travis, yarn

.travis.yml

@@ -1,7 +1,6 @@
 ---
 language: node_js
-node_js:
-  - "4"
+node_js: lts/carbon
 
 sudo: false
 dist: trusty
@@ -14,7 +13,6 @@ cache:
   directories:
     - $HOME/.cache # includes bowers cache
 
-env:
 env:
   global:
     - DEBUG="auto-dist-tag"
@@ -23,6 +21,9 @@ env:
     # as well as latest stable release (bonus points to beta/canary)
     - EMBER_TRY_SCENARIO=ember-lts-2.4
     - EMBER_TRY_SCENARIO=ember-lts-2.8
+    # final LTS for 2.x line:
+    - EMBER_TRY_SCENARIO=ember-2.18
+    # 3.x +
     - EMBER_TRY_SCENARIO=ember-release
     - EMBER_TRY_SCENARIO=ember-beta
     - EMBER_TRY_SCENARIO=ember-canary

config/ember-try.js

@@ -3,6 +3,7 @@
 /* eslint-env node */
 
 module.exports = {
+  useYarn: true,
   scenarios: [
     {
       name: 'ember-lts-2.4',
@@ -36,6 +37,22 @@ module.exports = {
         }
       }
     },
+    {
+      name: 'ember-2.18',
+      bower: {
+        dependencies: {
+          'ember': 'components/ember#2.18'
+        },
+        resolutions: {
+          'ember': '2.18'
+        }
+      },
+      npm: {
+        devDependencies: {
+          'ember-source': null
+        }
+      }
+    },
     {
       name: 'ember-release',
       bower: {