Merge pull request #4 from cytopia/ci

Add linting stage for CI

.travis.yml

@@ -41,6 +41,7 @@ install:
 ### Check generation changes, build and test
 ###
 before_script:
+  - make lint
   - while ! make build TAG=${VERSION}; do sleep 1; done
   - while ! make test TAG=${VERSION}; do sleep 1; done
   - git diff --quiet || { echo "Build Changes"; git diff; git status; false; }