Indicate where outputs of run.sensitivity.analysis() are saved.

[Aariq]

Bug Description

sensitivity.results...Rdata, and sensitivity.output...Rdata are saved to outdir/ and the plots are saved to outdir/pft/<pftname>/. This isn't in the function documentation and it wasn't intuitive to me (I thought the function wasn't working because the plots weren't in the same place as the rest of the outputs until I looked at the source code).

Expected behavior

A few possibilities that would make sense to me (not mutually exclusive):

1. Print the file paths to the console
2. Include info about the filepaths in @details
3. Have the function return the filepaths invisibly

[Aariq]

Possibly related to #868?

[github-actions]

This issue is stale because it has been open 365 days with no activity.