TX2 深度学习环境搭建记录cmake从3.5升级到3.7.2

1.（参考https://askubuntu.com/questions/355565/how-do-i-install-the-latest-version-of-cmake-from-the-command-line/865294#865294）

The most common situation is when you want to install the latest version of cmake, but your Operating System's repositories are not updated. For example, in my case I have a laptop running Ubuntu 16.04, and when I executed the command sudo apt install cmake the installed version was 3.5.1; instead of, 3.12.3 which is the current version at cmake.org.

How can I get the latest version?

Well, we can install it by following one of this methods:

A. Building and Installing (recommended)

A-1. Uninstall the default version provided by Ubuntu's package manager:

sudo apt remove cmake
    sudo apt purge --auto-remove cmake

A-2. Go to the official CMake webpage, then download and extract the latest version. Update the version and build variables in the following command to get the desired version:

    version=3.12
    build=3
    mkdir ~/temp
    cd ~/temp
    wget https://cmake.org/files/v$version/cmake-$version.$build.tar.gz
    tar -xzvf cmake-$version.$build.tar.gz
    cd cmake-$version.$build/

A-3. Install the extracted source by running:

    ./bootstrap
    make -j4
    sudo make install

A-4. Test your new cmake version.

    $ cmake --version

Results of cmake --version:

    cmake version 3.12.X

    CMake suite maintained and supported by Kitware (kitware.com/cmake).

B. Using binary files (cmake-gui wont work well)

B-1. Uninstall the default version provided by Ubuntu's package manager as in A-1.

B-2. Go to the official CMake webpage（https://cmake.org/download/）, then download and install the latest .sh version in opt/cmake. Update the version and build variables in the following command to get the desired version:

    version=3.12
    build=3
    mkdir ~/temp
    cd ~/temp
    wget https://cmake.org/files/v$version/cmake-$version.$build-Linux-x86_64.sh 
    sudo mkdir /opt/cmake
    sudo sh cmake-$version.$build-Linux-x86_64.sh --prefix=/opt/cmake

B-3. Add the installed binary link to /usr/local/bin/cmake by running this:

    sudo ln -s /opt/cmake/bin/cmake /usr/local/bin/cmake

B-4. Test your new cmake version as in A-4.