title: Can anybody generate opencv.js?
body: <p>I can't generate OpenCV.js using this instructions: <a href="https://docs.opencv.org/master/d4/da1/tutorial_js_setup.html" rel="noreferrer">https://docs.opencv.org/master/d4/da1/tutorial_js_setup.html</a></p>
  
  <p>I have this error: </p>
  
  <blockquote>
    <p>CMake Error: CMake was unable to find a build program corresponding to
    "Unix Makefiles".  CMAKE_MAKE_PROGRAM is not set.  You probably need
    to select a different build tool.</p>
  </blockquote>
  
  <p>When I'm trying to execute:</p>
  
  <pre><code>python ./platforms/js/build_js.py build_js
  </code></pre>
  
  <p>Alright, guys! You can download opencv.js from sources (press F12) of this Page: <a href="https://docs.opencv.org/master/js_face_detection_camera.html" rel="noreferrer">https://docs.opencv.org/master/js_face_detection_camera.html</a></p>