autogen_global_target
---------------------

* The new variables :variable:`CMAKE_GLOBAL_AUTOGEN_TARGET`,
  :variable:`CMAKE_GLOBAL_AUTOGEN_TARGET_NAME`,
  :variable:`CMAKE_GLOBAL_AUTORCC_TARGET` and
  :variable:`CMAKE_GLOBAL_AUTORCC_TARGET_NAME` control the generation
  of global ``autogen`` and ``autorcc`` targets.
