chore(travis): run linter on Travis

.prettierignore

@@ -1,3 +1,5 @@
 node_modules/
 build/
 styleguide/
+package.json
+CHANGELOG.json

.travis.yml

@@ -0,0 +1,15 @@
+language: node_js
+
+node_js:
+  - 8
+
+script:
+  - yarn ci
+
+notifications:
+  email: false
+
+cache:
+  yarn: true
+  directories:
+    - "node_modules"

package.json

@@ -13,8 +13,10 @@
     "build:lib": "cross-env BABEL_ENV=lib babel --out-dir build src",
     "build:rollup": "cross-env BABEL_ENV=rollup rollup -c",
     "build:watch": "yarn build:lib --watch",
+    "ci": "yarn lint",
     "deploy:docs": "firebase deploy",
     "dev": "styleguidist server",
+    "lint": "eslint .",
     "prebuild": "shx rm -rf dist/*",
     "release": "standard-version && conventional-github-releaser -p angular && yarn build && yarn deploy:docs"
   },