DOC: Distinguish between different types of boolean indexing #10492
- [x] closes #10492
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`

Thanks @arw2019 .
This was a very helpful review.  I made the changes accordingly. would love to get a hacktoberfest tag if possible. #36837

 thanks @junjunjunk 