Merge pull request #47 from juwara0/travisVars

Update travis.yml with build variables and remove node stable build

.travis.yml

@@ -3,8 +3,7 @@ dist: trusty
 language: node_js
 
 node_js:
-- '8.1.2'
-- 'stable'
+- $PUBLISH_NODE_VERSION
 
 addons:
   apt:
@@ -30,8 +29,6 @@ env:
 
 matrix:
   fast_finish: true
-  allow_failures:
-  - node_js: 'stable'
 
 before_install:
 - npm config set spin false
@@ -63,7 +60,7 @@ deploy:
   on:
     all_branches: true
     condition: "$EMBER_TRY_SCENARIO = 'ember-default'"
-    node: '8.1.2'
+    node: $PUBLISH_NODE_VERSION
     tags: true
 
 after_deploy: