Add cpplint into continuous build.
diff --git a/.travis.yml b/.travis.yml
index bc6e621..e3c1ed4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -30,7 +30,8 @@
- cd -
before_script:
- - mkdir -p build && cd build && pwd
+ - travis_retry wget --quiet -O - https://raw.githubusercontent.com/cpplint/cpplint/master/cpplint.py | python - --root=src --recursive --filter=-build/include_subdir src examples
+ - mkdir -p build && cd build
- cmake .. -GNinja -DCMAKE_C_COMPILER=${CC_COMPILER} -DCMAKE_CXX_COMPILER=${CXX_COMPILER} -DCMAKE_BUILD_TYPE=${BUILD_TYPE}
script: