Document options for set_option()

[machow]

Looking at the docstrings and reference pages, I wasn't sure what options set_option() and get_option() support. In searching for them I followed this path:

• Look at set_option() docstring
• Look up set_option() on reference index, and click into it
• Look up get_option()
• Read plotnine.options source code, notice options are documented on this module
• Open this issue
• Look back at Reference index and notice the Options section lists out each plotnine.options piece

I wonder if two pieces might help shorten this journey:

1. mention on set_option() and get_option() that the documentation lives at plotnine.options.
2. mention in the Options section of the Reference index that the items are from plotnine.options

I think (2) is similar to what the Datasets section does in the reference, which seems to work well!

[has2k1]

1. mention on set_option() and get_option() that the documentation lives at plotnine.options

I agree.

2. mention in the Options section of the Reference index that the items are from plotnine.options

I'm not so happy that the options are global variables and mentioning plotnine.options makes it more explicit. I think the documentation should emphasise interacting with the options through get_option and set_option functions.

Maybe in the reference index we can further split the section into two tables; the options and then get/set functions.