Fix example docs and background width

[e10harvey]

Purpose

Fix the formatting of our readthedocs documentation. E.g., see https://opencsp.readthedocs.io/en/main/example/scene_reconstruction/config.html.

Summary of changes

Add css style to expand width of white background to entire screen.
Fix doc-string format such that lists include newlines between elements.

Implementation notes

Checked via ./make_docs.sh && open html/index.html

Submission checklist

• Target branch is develop, not main
• Existing tests are updated or new tests were added
• opencsp/test/test_DocStringsExist.py are verified to include this change or have been updated accordingly
• .rst file(s) under doc/ are verified to include this change or have been updated accordingly

Additional information

Please provide any additional information here.

[braden6521]

@e10harvey, this all looks good to me!