message: Unify cmake command for Linux & macOS on travis
diff: @@ -21,16 +21,19 @@ install:
  - |
  if [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then
  wget https://cmake.org/files/v3.8/cmake-3.8.2-Linux-x86_64.tar.gz
  - tar -xvzf cmake-3.8.2-Linux-x86_64.tar.gz
  + CMAKE_DIR=${TRAVIS_BUILD_DIR}/cmake && mkdir ${CMAKE_DIR}
  + tar -xvzf cmake-3.8.2-Linux-x86_64.tar.gz --strip-components=1 -C ${CMAKE_DIR} # extract from inside the top-level directory to CMAKE_DIR
  + export PATH=${CMAKE_DIR}/bin:${PATH}
  pyenv global system 3.6 # Workaround for travis-ci/issues/8363
  sudo apt-get update -q
  sudo apt-get install libboost-all-dev libopencv-dev -y
  else
  brew install cmake || brew upgrade cmake
  brew install boost
  - /usr/bin/yes | pip2 uninstall numpy # see: https://github.com/travis-ci/travis-ci/issues/6688
  + /usr/bin/yes | pip2 uninstall numpy # see: travis-ci/issues/6688
  brew install opencv
  fi
  + - cmake --version
  before_script:
  - mkdir build
  