I ran into "too many files open" when attempting to load the plugins.

Try increasing the ulimit.

What's the status of this? The content on jenkins.io is still hard-coded and slowly becoming out of date.

Just sent in a bunch of changes for improvements to this whole structure:
Submitted PR10 to backend-extender to create the appropriate folder
Added new changes to pipeline-steps-doc-generator with the changes needed to run a job successfully generating the documentation. Check out that repo for all the changes..

There were a few suggestions for pipeline-steps-doc-generator, and it is now checking every plugin that's found in the Jenkins `public` maven repository. I'm recording the documentation as it comes from .jelly files so any changes are on a plugin basis. The header can be changed as needed; I followed the "simple-template" as a starting point.

Waiting in the wings:
PR to jenkinsio (have written and would definitely need a review) after the pipeline-steps-doc-generator is added as a job, and run successfully once.

Created a PR for handling the automatic documentation generation. All reviews are welcome.

PR merged. Closing and using INFRA-607 as the tracking ticket since there are a few pieces of infrastructure that need to be addressed.