docs(menu): add missing position modes

[Splaktar]

PR Checklist

Please check that your PR fulfills the following requirements:

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[x] Documentation content changes
[ ] Infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Most all of the new position modes are missing from the documentation. There are many typos. The explanations are not clear.

Issue Number:
Fixes #5150.

What is the new behavior?

add docs for all of the position modes
fix typos
clarify text descriptions
provide more examples
explain default positioning
fix old URL

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

N/A