Check assimp.dir folder.

.travis.yml

@@ -49,7 +49,7 @@ after_success:
   - cd ${TRAVIS_BUILD_DIR}
   - pwd
   - ls
-  - cd code/CMakeFiles/;ls
+  - cd code/CMakeFiles/;ls assimp.dir
   - lcov --directory code/CMakeFiles/assimp.dir/ --capture --output-file coverage.info
   - lcov --remove coverage.info 'contrib/*' '/usr/*' --output-file coverage.info
   - lcov --list coverage.info