Feature: Add guidebook page that overviews using badges in a package readme

[lwasser]

this was inspired by @Zeitsperre comment around how the python version badge is created

there are two ways of indicating the compatibility of Python for a package; classifiers is for users (i.e. for the badge) and requires-python is for pip (for the dependency resolver)

badges reference the colored indicators of a package's status often found in the readme file. See xclim readme as an example.

we'd want to add information about

• adding core badges that indicate things such as:
• what versions of python a package supports
• pypi and conda-forge publication versions
• github actions pass/fail
• documentation pass/fail.
  if someone wants to start this page focusing on just a specific type of badge and how to create it that is also welcome! we can then chip away at building out the page