From the discussion with @timbl yesterday, the decision was made that the current container .meta mechanism is not very useful, and may be counter-intuitive to developers, and so should be removed.

• Currently, a PATCH or a PUT with a body to a solid container puts the triples in the request body into that container's .meta resource. Disable/remove that logic.
• The contents of a container's .meta resource gets appended to the container listing no a GET to that container. Disable/remove logic.
• Update Solid spec to reflect this change.