Reduce distribution size

[TomAugspurger]

xref conda/conda#6756 (comment)

We include a bunch of SAS, CSV, pickle, etc. files in the distributions that are only used for testing. I think these could be excluded (and the tests rewritten to skip if the files aren't present).

[jreback]

can u see the total size
these are all very small

[TomAugspurger]

Yeah I had to run before finishing the post. I think it’s about 20% of the sdist. I’ll edit in details.

[jreback]

yeah i guess could trim the sas a bit