Upgrade CMake on OS X

Author: nox

.travis.yml

@@ -13,7 +13,10 @@ env:
   - FEATURES="--features debugmozjs"
 
 before_install:
+- if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update; fi
 - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew install ccache; fi
+- if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew outdated cmake || brew upgrade cmake; fi
+- cmake --version
 
 script:
   - ccache -z