Allow to exclude examples from build by setting ATOMIC_CPLUSPLUS_EXAMPLES in parent project.

CMakeLists.txt

@@ -78,7 +78,9 @@ add_definitions(${ATOMIC_DEFINITIONS})
 add_subdirectory(Source)
 
 if (ATOMIC_DESKTOP AND ATOMIC_DEV_BUILD)
-    set (ATOMIC_CPLUSPLUS_EXAMPLES 1)
+    if (NOT DEFINED ATOMIC_CPLUSPLUS_EXAMPLES)
+        set (ATOMIC_CPLUSPLUS_EXAMPLES 1)
+    endif ()
     if (ATOMIC_CPLUSPLUS_EXAMPLES)
         add_subdirectory(Submodules/AtomicExamples/FeatureExamples/CPlusPlus)
     endif()