title: CMAKE finds package but does not link libraries
body: <p>I'm trying to compile a project with CMAKE and make with MinGW32-make.exe.  My CMakeLists.txt looks like so:</p>
  
  <pre><code>#####################################
  cmake_minimum_required (VERSION 3.0) 
  project (TestProject)
  find_package(OpenCV REQUIRED)
  include_directories(${OPENCV_INCLUDE_DIR})
  add_executable (main.exe main.cpp)
  #####################################
  </code></pre>
  
  <p>Running "CMAKE -G "MinGW Makefiles" runs fine, but when I try to make with "MinGW32-make.exe" I get the following error:</p>
  
  <pre><code>25:39: fatal error: opencv2/highgui/highgui.hpp: No such file or directory
   #include "opencv2/highgui/highgui.hpp"
  </code></pre>
  
  <p>When I look in the Makefile, I can't find the text "OpenCV" anywhere.  In which file is the OPENCV directory supposed to be identified?</p>