Revise scope and out-of-scope

[csarven]

Resolves https://github.com/solid/solid-wg-charter/issues/9 based on feedback in issue and agreement in https://github.com/solid/specification/blob/main/meetings/2023-05-31.md#scope-needs-to-be-tightly-defined-with-narrow-focus .

The first item leaves sufficient space for (new) features that are reasonably applicable under the Solid Protocol to be worked on. The second item essentially covers Notes, including e.g., Primers, Best Practices and Guidelines.

Noting here (as discussed in the 2023-05-31 meeting):

• in Scope does not entail that the WG will necessarily agree to start a new work item, with the exception of Out of Scope works.
• for Out of Scope items, there are other Groups (in/out of W3C) that'd deemed to be more fit to continue those kinds of works.

[csarven]

The group agreed to merge this PR in 2023-06-07 https://github.com/solid/specification/blob/main/meetings/2023-06-07.md#revise-scope-and-out-of-scope . Also with the understanding that deliverables are not conflicting with out of scope, e.g., WebID (once approved).