title: How to install CLI11?
body: <p>I use the <a href="https://github.com/CLIUtils/CLI11/blob/master/README.md#install" rel="nofollow noreferrer">5th method</a> to install <a href="https://github.com/CLIUtils/CLI11" rel="nofollow noreferrer">CLI11</a>.</p>
  <p>I test the <a href="https://github.com/CLIUtils/CLI11/tree/master/test_package" rel="nofollow noreferrer"><code>../CLI11/test_package</code></a> and want to use <code>find_package</code> to include <code>CLI11</code> but failed.</p>
  <p>The content of CMakeLists.txt.</p>
  <pre><code>project(PackageTest CXX)
  cmake_minimum_required(VERSION 3.1)
  
  find_package(CLI11 CONFIG REQUIRED)
  ...
  
  </code></pre>
  <p>I got the error as follow:</p>
  <pre><code>CMake Error at CMakeLists.txt:6 (find_package):
    Could not find a package configuration file provided by &quot;CLI11&quot; with any of
    the following names:
  
      CLI11Config.cmake
      cli11-config.cmake
  
    Add the installation prefix of &quot;CLI11&quot; to CMAKE_PREFIX_PATH or set
    &quot;CLI11_DIR&quot; to a directory containing one of the above files.  If &quot;CLI11&quot;
    provides a separate development package or SDK, be sure it has been
    installed.
  
  
  -- Configuring incomplete, errors occurred!
  ...
  </code></pre>