ENH: add an option to enable Applications build

CMakeLists.txt

@@ -54,6 +54,7 @@ INCLUDE (${CMAKE_ROOT}/Modules/CMakeBackwardCompatibilityCXX.cmake)
 
 OPTION(BUILD_TESTING  "Build testing." OFF)
 OPTION(BUILD_EXAMPLES "Build the Examples directory." OFF)
+OPTION(BUILD_APPLICATIONS "Build applications" OFF)
 
 INCLUDE(${CMAKE_ROOT}/Modules/Dart.cmake)
 CONFIGURE_FILE(CMake/CTestCustom.cmake.in CTestCustom.cmake)
@@ -255,6 +256,10 @@ INCLUDE_DIRECTORIES(
 ADD_SUBDIRECTORY(Utilities)
 ADD_SUBDIRECTORY(Code)
 
+IF (BUILD_APPLICATIONS)
+  ADD_SUBDIRECTORY(Applications)
+ENDIF (BUILD_APPLICATIONS)
+
 IF (BUILD_TESTING)
   ADD_SUBDIRECTORY(Testing)
 ENDIF (BUILD_TESTING)