Clean return for specific analysis if a specific AM turned off in model

[pwolfram]

Should we add a check on whether the needed AM for the analysis was turned on?

For example, we will always need timeSeriesStats, but of course we'll want specific AM's for metrics such as the OHC, MOC, etc.

cc @milenaveneziani and @xylar

[xylar]

@pwolfram, yes, I think this is important. It's a subset of #18, and I think it makes sense to have more specific issues that can be addressed with a single PR like this one and as opposed to #18.

[pwolfram]

This should be addressable via improvements proposed in #127, correct @xylar?

[pwolfram]

On second thought we may need something else but it may be worthwhile building this functionality into the task base while we are thinking about what constitutes a particular "analysis".

[xylar]

#127 / #128 don't address this directly but the setup_and_check function is intended precisely to address this issue. Together with some checks that @milenaveneziani has put into #139, I think this should be able to be addressed.

[xylar]

Addressed by #129 and some subsequent clean up.