Show execution time of cell after successful completion

[jyc]

It'd be nice to know how long a cell took to execute even if it succeeds. Currently the timer is hidden as soon as the cell's status changes to "Evaluated."

[josevalim]

I believe you can mouse over the status, and then the time will show up

[jyc]

Thanks for the tip! That helps a lot. Unfortunately it looks like the timer goes away as soon as the cell becomes Stale, but at least I can look at it while the cell is still in the green Evaluated state.

[josevalim]

@jonatanklosko we should probably keep the timer when Stale as well, right?

[jonatanklosko]

Sounds good, same for aborted. Done in cc92a6d.