macOS: Installation of app bundles should be smarter than install(DIRECTORY)
Currently, installing an application bundle boils down to an
install(DIRECTORY). This may copy build-tree-specific files which need to be in the bundle for build-tree usage. Instead, CMake should install only the application itself and the
This causes problems because attempts to overwrite the build-tree bundle copy of a file may be thwarted by commit 4e514a5e (tags/v2.6.0~583, see #3349 (closed)). In addition, any binaries which may be in there for other reasons are not updated for install name dirs or install rpaths.
This likely requires a policy in case anyone was relying on the existing bundle installation to copy these files around.