title: cmake-Unable to find the requested Boost libraries
body: <p>I want to use CGAL libraries , I'm using :
  CGAL 4.10 ,Microsoft visual studio 2013 , CMake 3.9.3 , boost 1.65, QT creator 4.3.1</p>
  
  <p>while Configuring CGAL using Cmake , it is showing the following errors:</p>
  
  <pre><code>Looking for pthread.h
  Looking for pthread.h - not found
  Found Threads: TRUE  
  CMake Error at C:/Program Files/CMake/share/cmake-3.9/Modules/FindBoost.cmake:1902 (message):
  Unable to find the requested Boost libraries.
  
  Unable to find the Boost header files.  Please set BOOST_ROOT to the root
  directory containing Boost or BOOST_INCLUDEDIR to the directory containing
  Boost's headers.
  Call Stack (most recent call first):
  cmake/modules/CGAL_SetupBoost.cmake:21 (find_package)
  cmake/modules/CGAL_SetupDependencies.cmake:85 (include)
  CMakeLists.txt:681 (include)
  
  
  Boost include:     Boost_INCLUDE_DIR-NOTFOUND
  Boost libraries:   
  Boost definitions: 
  USING BOOST_VERSION = '..'
  == Detect external libraries (DONE) ==
  
  == Write compiler_config.h ==
  Performing Test CGAL_CFG_DENORMALS_COMPILE_BUG - Success
  Performing Test CGAL_CFG_FPU_ROUNDING_MODE_UNWINDING_VC_BUG - Success
  Performing Test CGAL_CFG_IEEE_754_BUG - Success
  Performing Test CGAL_CFG_ISTREAM_INT_BUG - Success
  Performing Test CGAL_CFG_MATCHING_BUG_5 - Success
  Performing Test CGAL_CFG_MATCHING_BUG_6 - Failed
  Performing Test CGAL_CFG_MATCHING_BUG_7 - Failed
  Performing Test CGAL_CFG_MATCHING_BUG_8 - Success
  Performing Test CGAL_CFG_NESTED_CLASS_FRIEND_DECLARATION_BUG - Failed
  Performing Test CGAL_CFG_NO_LIMITS - Success
  Performing Test CGAL_CFG_NO_NEXTAFTER - Failed
  Performing Test CGAL_CFG_NO_STL - Success
  Performing Test CGAL_CFG_NUMERIC_LIMITS_BUG - Success
  Performing Test CGAL_CFG_OUTOFLINE_MEMBER_DEFINITION_BUG - Success
  Performing Test CGAL_CFG_TEMPLATE_IN_DEFAULT_PARAMETER_BUG - Success
  Performing Test CGAL_CFG_TYPENAME_BEFORE_DEFAULT_ARGUMENT_BUG - Success
  Performing Test CGAL_CFG_USING_BASE_MEMBER_BUG_2 - Success
  == Write compiler_config.h (DONE) ==
  
  
  CMake Error: The following variables are used in this project, but they     are set to NOTFOUND.
  Please set them or make sure they are set and tested correctly in the  CMake files:
  Boost_INCLUDE_DIR (ADVANCED)
  used as include directory in directory C:/dev/CGAL-4.10/src/CGAL
  used as include directory in directory C:/dev/CGAL-4.10/src/CGAL
  used as include directory in directory C:/dev/CGAL-4.10/src/CGAL_Core
  used as include directory in directory C:/dev/CGAL-4.10/src/CGAL_Core
  used as include directory in directory C:/dev/CGAL-4.10/src/CGAL_ImageIO
  used as include directory in directory C:/dev/CGAL-4.10/src/CGAL_ImageIO
  </code></pre>
  
  <p>I added Boost_INCLUDE_DIR,BOOST_ROOT manually to environment vairables</p>
  
  <p>Boost_INCLUDE_DIR=C:\dev\boost_1_65_0;BOOST_ROOT=C:\dev\boost_1_65_0</p>
  
  <p>I tried many versions of boost ,cmake and cgal with visual sutudio 2015 , 2013 and non of the was working</p>
  
  <p>I appreciate any help.thank you</p>