* Trying to fix ninja build on travis

.travis.yml

@@ -11,13 +11,15 @@ before_install:
   # Linux
   - if [ ["$TRAVIS_OS_NAME" == "linux"] && ["$CXX" == "g++"] ]; then export CXX="g++-4.8" CC="gcc-4.8"; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo add-apt-repository -y "deb http://archive.ubuntu.com/ubuntu/ trusty main universe"; fi
+  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo apt-get install software-properties-common; fi
+  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo add-apt-repository ppa:george-edison55/cmake-2.9; fi
+  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo apt-get install --only-upgrade cmake; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo apt-get update -qq; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo apt-get install root-system -qq; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo apt-get clean; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then cd && wget https://www.dropbox.com/s/8hxjkd6twdsv5fi/geant4_install_new.tar.gz; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then tar -xf geant4_install_new.tar.gz; fi
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then source ~/geant4_install/share/Geant4-10.1.2/geant4make/geant4make.sh; fi
-
   # OSX 
   - if [ "$TRAVIS_OS_NAME" == "osx" ]; then brew update; fi 
   - if [ "$TRAVIS_OS_NAME" == "osx" ]; then brew install homebrew/science/root; fi