Allow the ability to choose to compile against boost libs statically.

CMakeLists.txt

@@ -26,6 +26,7 @@ configure_file ("${OpenMW_SOURCE_DIR}/Docs/mainpage.hpp.cmake" "${OpenMW_SOURCE_
 
 option(MYGUI_STATIC "Link static build of Mygui into the binaries" FALSE)
 option(OGRE_STATIC  "Link static build of Ogre and Ogre Plugins into the binaries" FALSE)
+option(BOOST_STATIC "Link static build of Boost into the binaries" FALSE)
 
 # Apps and tools
 option(BUILD_ESMTOOL "build ESM inspector" ON)
@@ -196,6 +197,10 @@ if (Boost_VERSION LESS 104900)
     set(BOOST_COMPONENTS ${BOOST_COMPONENTS} wave)
 endif()
 
+IF(BOOST_STATIC)
+    set(Boost_USE_STATIC_LIBS   ON)
+endif()
+
 find_package(OGRE REQUIRED)
 find_package(MyGUI REQUIRED)
 find_package(Boost REQUIRED COMPONENTS ${BOOST_COMPONENTS})