add Just Workplace entry to values

Created by: shrouxm

I've found this to be generally true, and think we are working towards making it more true, so I took a stab at writing it down!

I'm less sure about including the examples. I think they're really helpful to make concrete what we mean by the more abstract values, and also help prove that these aren't just things that we say.

This is intended to be a starting point for discussion of what our goals are here and how we want to communicate them, though I would be OK with including it in the handbook as is.