Don't drop NAs by default in _load_time_variables and analysis.setup()

Analysis.setup() drop_na defaults to True (actually, you can trace this back all the way to _load_time_variables in variables.io)

Given that there will be a DropNA transformation (not implemented yet), shouldn’t the default be False?

I need to have it set to False for fitlins (so that NAs can be imputed to the mean on occasion) but @effigies needs to drop nas for his model to run and currently there is no way to do that through the model itself. Unless we were to pass it as a kwargs in the Input section, but that seems hacky.

I suggest drop na should not occur by default, and the user should have to specify this through the BIDS-StatsModel. I would be okay with just reading kwargs from Inputs as a temporary solution though.

[effigies]

Okay. Sorry I’m being a bit slow. Trying to run some stuff. Will get back to testing when I’ve got some results, or the next thing breaks.

[tyarkoni]

I have an updated changelog in a local branch; we can write a short migration guide later. While there are a lot of changes, the vast majority are relevant outside of the layout module, and so far I think we’re probably the only ones actually using anything in Analysis. I think other than renaming entities and maybe changing a few initialization arguments, the update to 0.7 should be fairly minimal for most users.