chore: build before npm test

Author: marionebl

.travis.yml

@@ -5,4 +5,8 @@ node_js:
   - '4'
 before_install:
   - npm i -g npm
+before_script:
+  - npm run build
+script:
+  - npm test
 after_success: npm run coveralls

appveyor.yml

@@ -18,4 +18,5 @@ clone_depth: 1
 test_script:
   - node --version
   - npm --version
+  - npm run build
   - npm test