Update from 2.8.5 to 2.9.3

[shaunagm]

Opening this PR on behalf of @Jason94. We've had tons of trouble with psycopg2-binary, maybe updating to the most recent version will fix some of them.

[SorenSpicknall]

I'm generally in favor of keeping deps updated, but has this been tested locally to see if it resolves any of the installation issues we're going after?

[shaunagm]

I think we'd have to run another install fest to see that - most of the people who had problems fixed them.

Alternatively, I could investigate what it would take (time and money-wise) to test the install process on 3-5 setups every X days (or every time we merge to master) and then see whether this helps us successfully execute a parsons install on a setup that isn't currently working.