title: How to use the wanted version of OpenCV if there are more?
body: <p>I have an application that uses OpenCV 2.4.9 and now I want to test OpenCV 3.0.0-beta. I have changed to the tag 3.0.0-beta and build the library. I have installed it and now I have 3 versions of OpenCV installed 2.4.8, 2.4.9 and 3.0.0-beta. Is there a way to choose the version I want?</p>
  
  <p>The application is written in C++ and build using cmake. This is the part of code that makes the linking:</p>
  
  <pre><code># ...
  find_package(OpenCV REQUIRED)
  
  include_directories(${OpenCV_INCLUDE_DIRS})
  
  add_executable(${EXECUTABLE_NAME}
      # ...
  )
  
  target_link_libraries(${EXECUTABLE_NAME} ${OpenCV_LIBS})
  # ...
  </code></pre>
  
  <p>Any help in choosing the version of OpenCV, please?</p>