GH1230 Improve types for pd.options.display.* properties

[mike-flowers-airbnb]

• Closes Type checks for pd.options.display.* are not accurate #1230
• Tests added: Please use assert_type() to assert the type of any return value

Updated based off documentation in config_init.py

Let me know if you'd like me to update the second test to also use assert_type on each value.

[Dr-Irv]

Changes in tests. I don't have time right now to verify the changes to the types in Display - will do that in next review.

[loicdiridollou]

One minor request as we are already touching the code here, otherwise looking in line with the pandas docs.

[Dr-Irv]

thanks @mike-flowers-airbnb