Update cmake version without default setting in ubuntu

From https://askubuntu.com/questions/829310/how-to-upgrade-cmake-in-ubuntu

1. Check your current version with cmake --version
2. Uninstall it with sudo apt remove cmake
3. Visit https://cmake.org/download/ and download the latest binaries
   • In my case cmake-3.6.2-Linux-x86_64.sh is sufficient
4. chmod +x /path/to/cmake-3.6.2-Linux-x86_64.sh (use your own file location here, but chmod makes the script executable)
5. sudo /path/to/cmake-3.6.2-Linux-x86_64.sh (you'll need to press y twice)
   The script installs to /opt/cmake-3.6.2-Linux-x86_64 so in order to get the cmakecommand, make a symbolic link:
6. sudo ln -s /opt/cmake-3.6.2-Linux-x86_64/bin/* /usr/local/bin
   Test your results with cmake --version