Build an executable as an Application Bundle on OS X or iOS.

When this property is set to TRUE the executable when built on OS X or iOS will be created as an application bundle. This makes it a GUI executable that can be launched from the Finder. See the MACOSX_FRAMEWORK_INFO_PLIST target property for information about creation of the Info.plist file for the application bundle. This property is initialized by the value of the variable CMAKE_MACOSX_BUNDLE if it is set when a target is created.