MET trigger hypo, ctest, and menu interface
This MR includes code for the MET trigger hypo, its interface with the trigger menu prototype, and the required ctests.
This branch also has !20031 (merged) merged into it to enable monitoring of the met hypo, and to fix a broken muon ctest.
Tagging codeveloper @mronzani, and watchers @fpastore and @tbold.