as enabling the hardened runtime and notarizing executables and disk images containing
them. This change provides a plist file to be embedded, and modifies the linker flags
for macOS targets in order to include the plist in the binary. This is done to the
Mach O executable in a backwards-compatible way, and has been tested as far back as
macOS 10.12 High Sierra.
Note: expect to carry this forward to 'next' branch; however this is being applied
to current official release master version 5.6.0 so that release disk images can be
notarized.
