Declaring the use of C++11 features

[vins31]

In order to compile with gcc 4.8.2 I had to add set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11") in my CMakeLists.txt

Since the former generation of comiplers require -std=c++0x a better idea would be to use this solution: http://stackoverflow.com/a/25836953