actually add vendor folder

vendor/raylib/cmake/BuildOptions.cmake

@@ -0,0 +1,18 @@
+if(${PLATFORM} MATCHES "Desktop" AND APPLE)
+  if(MACOS_FATLIB)
+      if (CMAKE_OSX_ARCHITECTURES)
+          message(FATAL_ERROR "User supplied -DCMAKE_OSX_ARCHITECTURES overrides -DMACOS_FATLIB=ON")
+      else()
+          set(CMAKE_OSX_ARCHITECTURES "x86_64;i386")
+      endif()
+  endif()
+endif()
+
+# This helps support the case where emsdk toolchain file is used
+# either by setting it with -DCMAKE_TOOLCHAIN_FILE=<path_to_emsdk>/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake
+# or by using "emcmake cmake -B build -S ." as described in https://emscripten.org/docs/compiling/Building-Projects.html
+if(EMSCRIPTEN)
+    SET(PLATFORM Web CACHE STRING "Forcing PLATFORM_WEB because EMSCRIPTEN was detected")
+endif()
+
+# vim: ft=cmake