title: CMake options for Interfacing Qt 5.2.1 (MSVC 2012) with OpenCV
body: <p>I'm trying to make OpenCV 2.4.9 work with Qt 5.2.1 (MSVC 2012). 
  My question is that is it necessary to build the OpenCV libraries from scratch to make them work with QT (Since a pre compiled version with VC 11 is already provided). If this is not the case, how should  I build my OpenCV library with CMake? Should I enable the 'WITH_QT' option or not?</p>
  
  <p>I'm working on windows 7.</p>