* Testing OSX on travis

.travis.yml

@@ -4,16 +4,20 @@ compiler:
   - gcc
   - clang
 
+os:
+  - linux
+  - osx
+
 before_install:
-  - sudo add-apt-repository -y "deb http://archive.ubuntu.com/ubuntu/ trusty main universe"
-  - sudo apt-get update -qq
-  - sudo apt-get install root-system -y
-  - if [ "$CXX" == "clang++" ]; then sudo add-apt-repository -y ppa:h-rayflood/llvm; fi 
+  # Linux
+  - if ["TRAVIS_OS_NAME" == "linux"]; sudo add-apt-repository -y "deb http://archive.ubuntu.com/ubuntu/ trusty main universe"; fi
+  - if ["TRAVIS_OS_NAME" == "linux"]; sudo apt-get update -qq; fi
+  - if ["TRAVIS_OS_NAME" == "linux"]; sudo apt-get install root-system -y; fi
+  # OSX 
+  -if ["TRAVIS_OS_NAME" = "osx"]; brew install homebrew/science/root; fi
+  -if ["TRAVIS_OS_NAME" = "osx"]; brew install homebrew/science/geant4; fi    
 
 install:
-  # clang 3.4
-  - if [ "$CXX" == "clang++" ]; then sudo apt-get install --allow-unauthenticated -qq clang-3.4; fi
-  - if [ "$CXX" == "clang++" ]; then export CXX="clang++-3.4"; fi
 
 script:
   - cd NPLib 
@@ -34,5 +38,4 @@ branches:
   only:
     - NPTool.2.dev
 
-os:
-  - linux
+