mon: use make install.
mon: add (crap) test.
mongroup 0.4.0 (new formula)

Closes #26020.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
nexus 2.7.2-03

Closes #27050.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>