Expand "getting started" docs to discuss type hints in more detail #6226
This pull request expands our "getting started" docs so they discuss how to use type hints in more detail.
In general, I'm hoping this pull request will accomplish two main things:
Here's a list of specific changes I made:
@JukkaL -- I added in a section about Optional types, as suggested. I also tried adding in some discussion of Tuple, but everything I tried adding felt a little bloated. I think as a compromise, what I'll do is submit a follow-up diff where I expand the "built-in types" page and have the "getting started" page directly link to that.