Decide what to do about permissions links in help topics

Problem/Motivation

On #3041924: [META] Convert hook_help() module overview text to topics, we are converting hook_help() module overviews to help topics.

A question has come up on at least one child issue: When the Help module displays a module overview page generated from a hook_help() implementation, it adds links at the bottom of the page automatically to the designated admin page for the module, as well as the permissions page section for the module (if the module has its own permissions).

In the new help topics system, we will not have a one-to-one correspondence between modules and topics, so we cannot add those links automatically. We need to figure out what to do about it.

Proposed resolution

For configuration page links, cover them in the text (because we will be describing tasks and should link to the page where the task is done).

For permissions links, we need to decide what to do (which is the point of this issue). Possible things we could do:

1. Don't put the links in at all. This would mean losing a possibly important bit of help functionality that we had in the old system.
2. Add a link in the text of the topic that describes the task related to the permissions.
3. Mention the needed permissions to accomplish each task in each task topic, but don't link to the permissions page. Instead make sure there is a topic in the help system about configuring permissions.
4. As a variation on that, we could make the permission mention in text link to the how to set permissions topic, or to the section of the permissions page for the module.

Remaining tasks

1. Decide what to do.
2. Make sure the child issues of #3041924: [META] Convert hook_help() module overview text to topics follow that decision, by updating each issue and the child issue template with this review instruction.

User interface changes

TBD

API changes

None.

Data model changes

None.

Release notes snippet