title: Configure contribution module with OpenCV 3.0 by CMake
body: <p>I am trying to configure the contribution file with OpenCV 3.0 to use SIFT and SURF algorithm. I am following this with CMake-gui; <a href="https://github.com/itseez/opencv_contrib" rel="nofollow">https://github.com/itseez/opencv_contrib</a></p>
  
  <p>I set up followings on the CMake GUI; 
  where is the source code: C:/opencv/sources
  where to build binaries: C:/opencv/sources/modules/core</p>
  
  <p>But whenever try to do this, it returns following error;</p>
  
  <p>The CXX compiler identification is unknown
  The C compiler identification is unknown
  CMake Error at CMakeLists.txt:88 (project):
    No CMAKE_CXX_COMPILER could be found.</p>
  
  <p>CMake Error at CMakeLists.txt:88 (project):
    No CMAKE_C_COMPILER could be found.</p>
  
  <p>Configuring incomplete, errors occurred!
  See also "C:/opencv/sources/modules/core/CMakeFiles/CMakeOutput.log".
  See also "C:/opencv/sources/modules/core/CMakeFiles/CMakeError.log".</p>
  
  <p>Could anyone please help me on this to go forward? </p>
  
  <p>Thank you so much! Much appreciated.
  Best,</p>