Customization docs page links to "Markdown package" are broken

[lancegoyke]

The Customization page in the docs makes reference to the "Markdown" package. These links are broken at the time of submitting this issue.

I'm not sure if the package was renamed or just moved, but here's an example:

This function uses the Markdown package for trans-compilation.

I'll try to fix whatever links I see as I'm going through the docs and submit pull requests.

[nicorellius]

Looks like this PR should be accepted. The live docs site/page still shows incorrect URL:

https://neutronx.github.io/django-markdownx/customization/#markdownx_markdownify_function