Bug 535269: Allow attributes on enumerators

C++17 feature.
Implementation and tests.

Change-Id: Idafe4ca41058e8387aeae9a27f028677c62245c0
Signed-off-by: Hansruedi Patzen <hansruedi.patzen@hsr.ch>
Signed-off-by: Thomas Corbat <tcorbat@hsr.ch>
6 files changed