refactor(cmake): split CMakeLists into modules (#1587)

cmake/macros/macos.cmake

@@ -0,0 +1,16 @@
+# macos specific macros
+
+# ADD_FRAMEWORK: args = `fwname`, `appname`
+macro(ADD_FRAMEWORK fwname appname)
+    find_library(FRAMEWORK_${fwname}
+            NAMES ${fwname}
+            PATHS ${CMAKE_OSX_SYSROOT}/System/Library
+            PATH_SUFFIXES Frameworks
+            NO_DEFAULT_PATH)
+    if( ${FRAMEWORK_${fwname}} STREQUAL FRAMEWORK_${fwname}-NOTFOUND)
+        MESSAGE(ERROR ": Framework ${fwname} not found")
+    else()
+        TARGET_LINK_LIBRARIES(${appname} "${FRAMEWORK_${fwname}}/${fwname}")
+        MESSAGE(STATUS "Framework ${fwname} found at ${FRAMEWORK_${fwname}}")
+    endif()
+endmacro(ADD_FRAMEWORK)