Help: Document CMAKE_SYSTEM_APPBUNDLE_PATH variable

Help/manual/cmake-variables.7.rst

@@ -147,6 +147,7 @@ Variables that Change Behavior
    /variable/CMAKE_PROJECT_PROJECT-NAME_INCLUDE
    /variable/CMAKE_SKIP_INSTALL_ALL_DEPENDENCY
    /variable/CMAKE_STAGING_PREFIX
+   /variable/CMAKE_SYSTEM_APPBUNDLE_PATH
    /variable/CMAKE_SYSTEM_FRAMEWORK_PATH
    /variable/CMAKE_SYSTEM_IGNORE_PATH
    /variable/CMAKE_SYSTEM_INCLUDE_PATH

Help/variable/CMAKE_SYSTEM_APPBUNDLE_PATH.rst

@@ -0,0 +1,7 @@
+CMAKE_SYSTEM_APPBUNDLE_PATH
+---------------------------
+
+Search path for OS X application bundles used by the :command:`find_program`,
+and :command:`find_package` commands.  By default it contains the standard
+directories for the current system.  It is *not* intended to be modified by
+the project, use :variable:`CMAKE_APPBUNDLE_PATH` for this.