message: Enable RPATH on OS X
diff: @@ -6,6 +6,7 @@ set(MATERIALX_BUILD_VERSION 3)
  cmake_minimum_required(VERSION 3.1)
  set(CMAKE_CXX_STANDARD 11)
  set(CMAKE_POSITION_INDEPENDENT_CODE TRUE)
  +set(CMAKE_MACOSX_RPATH ON)
  option(MATERIALX_BUILD_PYTHON "Build the MaterialX Python package from C++ bindings. Requires Python 2.6 or greater." OFF)
  option(MATERIALX_GENERATE_DOCS "Create HTML documentation using Doxygen. Requires that Doxygen be installed." OFF)
  