Changing build folder so it doesn't conflict with BUILD file on OSX.
diff --git a/.travis.yml b/.travis.yml
index 2a5d41e..86b3cc5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,8 +11,6 @@
 
 script:
   - cmake --version
-  - mkdir build
-  - cd build
-  - cmake ..
-  - cmake --build . --target all
-  - CTEST_OUTPUT_ON_FAILURE=1 cmake --build . --target test
+  - cmake -H. -Bcmake_build
+  - cmake --build cmake_build --target all
+  - CTEST_OUTPUT_ON_FAILURE=1 cmake --build cmake_build --target test