Clean up issues that may cause the docs-lint
test to fail, such as trailing whitespace, no
EOF newline, blockquotes, etc

Adds MD010 (Hard tabs), MD012 (blank lines), MD029 (ordered
list prefix), MD030 (spaces after list markers), and fixes
remaining docs that were failing these tests

* Add deprecation warning to old integration
* Add user docs
* Add admin docs

- Move steps to new doc
- Move all concepts to different docs

Many code blocks are 4spaced, and they render in GitLab
without coloring as a result, even though they are
fenced with a language label. If in a list, other items
will render as being in a code block too, even if not
meant to. This fixes all these issues for many admin
docs (part 2)