Add node versions

Author: jessedobbelaere

.travis.yml

@@ -1,7 +1,9 @@
 language: node_js
 sudo: false
 node_js:
-  - "6"
+  - "8.4.0"
+  - "7.5.0"
+  - "6.4.0"
 install:
   - npm install
 script:

package.json

@@ -9,6 +9,9 @@
     "test": "mocha index.test",
     "release": "with-package git commit -am pkg.version && with-package git tag pkg.version && git push && npm publish && git push --tags"
   },
+  "engines": {
+    "node": ">=6.4.0"
+  },
   "repository": {
     "type": "git",
     "url": "git+https://github.com/jessedobbelaere/jira-smart-commit.git"