All munges now start with `<!-- BEGIN MUNGE:` and end with `<!-- END MUNGE:`.
This lets me (in a followup) filter them better to normalize contents during
verification of generated docs.
Adds cmd/mungedocs which is framework for processing
all files under docs/ and either verifying that no changes needed or
making in-place changes.
Did not reuse kube::util::gen-docs because that seemed to be
centered around handling added files, and this pass does not
add files.
Planned uses:
- table of contents automatic updating
- linkification
- internal link checker
- link-path-relativizer or absolutizer
- example file syncer
- header inserter.
Just table-of-contents updating in this PR.
Added Table of Contents to docs/networking.md.
Demonstrates use of new TOC generator presubmit.
Other docs will be added in future PRs.
Additional development will be needed to handle some
of the more complex cases.
