tasks waiting on xtriggers etc. are n=1

[hjoliver]

Tasks waiting on any kind of external triggers currently appear as "waiting" in the scheduler task pool, and are consequently seen as n=0 active tasks in the data store.

However, as argued in the n-distance window proposal they should be seen as n=1, because they are one graph edge downstream of the "active" triggers that they are waiting on. This should be literally true in the future once we can spawn tasks off of trigger events, but until then the data store should artificially show these tasks as n=1, not n=0.

Note this makes a difference (to what is seen in the UI) even in n=0 and n=1 windows.