Disable Mac builds because it's taking too long

Travis-CI throws a "The job exceeded the maximum time limit for jobs,
and has been terminated." before "brew upgrade python" has even
finished executing.

.travis.yml

@@ -25,20 +25,20 @@ matrix:
   #   env: NAME="conan" NAME_SUFFIX="conan" USE_CONAN=1
   #   script:
   #     - scripts/docker/docker_travis.sh "conan_base.docker"
-  - os: osx
-    compiler: clang
-    env: NAME="Apple macOS" NAME_SUFFIX="mac"
-    osx_image: xcode10.1
-    install:
-      - brew update
-      - /usr/bin/yes | pip2 uninstall numpy  # see https://github.com/travis-ci/travis-ci/issues/6688
-      - brew upgrade python
-      - brew upgrade
-      - brew install boost cmake bullet ffmpeg glm openal-soft qt5 sdl2 jack freetype
-      - export PATH="/usr/local/opt/qt/bin:$PATH"
-    script:
-      - mkdir -p "$TRAVIS_BUILD_DIR/build"
-      - ctest -VV -S "$TRAVIS_BUILD_DIR/cmake/ctest/script_ci.ctest"
+  # - os: osx
+  #   compiler: clang
+  #   env: NAME="Apple macOS" NAME_SUFFIX="mac"
+  #   osx_image: xcode10.1
+  #   install:
+  #     - brew update
+  #     - /usr/bin/yes | pip2 uninstall numpy  # see https://github.com/travis-ci/travis-ci/issues/6688
+  #     - brew upgrade python
+  #     - brew upgrade
+  #     - brew install boost cmake bullet ffmpeg glm openal-soft qt5 sdl2 jack freetype
+  #     - export PATH="/usr/local/opt/qt/bin:$PATH"
+  #   script:
+  #     - mkdir -p "$TRAVIS_BUILD_DIR/build"
+  #     - ctest -VV -S "$TRAVIS_BUILD_DIR/cmake/ctest/script_ci.ctest"
 
 notifications:
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