message: sanitize cmake build type
diff: @@ -22,6 +22,33 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake")
  include(ExternalProject)
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Wall -Wno-comment -Wno-sign-compare")
  +# In order to compile ngraph-tf with memory leak detection, run `cmake` with `-DCMAKE_BUILD_TYPE=Sanitize`.
  +# N.B.: This *will* crash python unit tests because ngraph-tf will be loaded "too late" via `dlopen`,
  +# so only use this with C++ tests.
  +# (In theory using `LD_PRELOAD` should address the python issue, but it doesn't appear to work on OS X, at least.)
  +# If there are any memory leaks, then upon running the binary a report will be automatically generated.
  +SET(CMAKE_CXX_FLAGS_SANITIZE
  + "${CMAKE_CXX_FLAGS_DEBUG} -fsanitize=address -D_LIBCPP_HAS_NO_ASAN -fsanitize-address-use-after-scope"
  + CACHE STRING "Flags used by the C++ compiler during sanitized builds."
  + FORCE )
  +SET(CMAKE_C_FLAGS_SANITIZE
  + "${CMAKE_C_FLAGS_DEBUG} -fsanitize=address -D_LIBCPP_HAS_NO_ASAN -fsanitize-address-use-after-scope"
  + CACHE STRING "Flags used by the C compiler during sanitized builds."
  + FORCE )
  +SET(CMAKE_EXE_LINKER_FLAGS_SANITIZE
  + "${CMAKE_EXE_LINKER_FLAGS_DEBUG} -fsanitize=address -D_LIBCPP_HAS_NO_ASAN -fsanitize-address-use-after-scope"
  + CACHE STRING "Flags used for linking binaries during sanitized builds."
  + FORCE )
  +SET(CMAKE_SHARED_LINKER_FLAGS_SANITIZE
  + "${CMAKE_SHARED_LINKER_FLAGS_DEBUG} -fsanitize=address -D_LIBCPP_HAS_NO_ASAN -fsanitize-address-use-after-scope"
  + CACHE STRING "Flags used by the shared libraries linker during coverage builds."
  + FORCE )
  +MARK_AS_ADVANCED(
  + CMAKE_CXX_FLAGS_SANITIZE
  + CMAKE_C_FLAGS_SANITIZE
  + CMAKE_EXE_LINKER_FLAGS_SANITIZE
  + CMAKE_SHARED_LINKER_FLAGS_SANITIZE)
  +
  # These variables are undocumented but useful.
  set(CMAKE_DISABLE_SOURCE_CHANGES ON)
  set(CMAKE_DISABLE_IN_SOURCE_BUILD ON)
  