chore(travis): add config

Author: gregberge

.travis.yml

@@ -0,0 +1,17 @@
+language: node_js
+
+node_js:
+  - 6
+  - 8
+
+before_install:
+  - curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.5.1
+  - export PATH="$HOME/.yarn/bin:$PATH"
+
+notifications:
+  email: false
+
+cache:
+  yarn: true
+  directories:
+    - "node_modules"