Update travis configuration for C++11 support

Signed-off-by: Jules Clero <julesx.clero@intel.com>

Author: clero

.travis.yml

@@ -4,9 +4,15 @@ compiler:
 #  - clang # not supported yet
 
 # install SWIG for bindings generation
+# and gcc 4.8.1 for c++11 features
 before_install:
+  - if [ "$CXX" == "g++" ]; then sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test; fi
   - sudo apt-get update -qq
+
+install:
   - sudo apt-get install -y swig
+  - if [ "$CXX" = "g++" ]; then sudo apt-get install -qq g++-4.8; fi
+  - if [ "$CXX" = "g++" ]; then export CXX="g++-4.8"; fi
 
 # how to build
 script: