should leaf-on / leaf-off be reported in events.out?

[infotroph]

As discussed live: leaf-on and leaf-off are essentially events with internally computed dates; for consistency we may want to report them in events.out.

Pro: especially useful for tracking leafGrowth, which is carbon that appears out of nowhere => seems good for all C balance violations to be understandable from reading events.out
Con: breaks the existing symmetry that events.out only contains things not set up in events.in

[mdietze]

I'll 1 up that and say that no only should phenology be in the events.out, but it would also be great to have the option to update the phenology dates in the events.in (which would restore symmetry)