message: Enable shared libraries build on Windows
diff: -cmake_minimum_required(VERSION 2.8.12)
  +cmake_minimum_required(VERSION 3.4.0)
  project(caf C CXX)
  include(CheckCSourceCompiles)
  @@ -20,10 +20,9 @@ if(APPLE AND NOT DEFINED CMAKE_MACOSX_RPATH)
  set(CMAKE_MACOSX_RPATH true)
  endif()
  -# Shared libs are currently not supported on Windows.
  -if(WIN32 AND NOT CAF_BUILD_STATIC_ONLY)
  - message(STATUS "CAF currently only supports static-only builds on Windows")
  - set(CAF_BUILD_STATIC_ONLY yes)
  +# Auto-export all symbols from Windows DLL
  +if(WIN32)
  + set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON)
  endif()
  if(CAF_BUILD_STATIC_RUNTIME)
  