Add sensorization vignette?

[ryantibs]

Should we add a vignette on sensorization? It's not clear to me whether we should.

I have the old sensorization examples (from the old modeltools vignette) saved in this Rmd, so can just start there if we deem this is a good thing to do.

[ryantibs]

There are now several vignettes, with more on the way, and already a good "advanced" example of sliding with the AR forecaster so ... I think this is no longer needed.