Update Chapter 6 - Editing System Metadata

[dvirlar2]

• Section 6.2 - Include either callback to where the code is for pids = c(pkg$metadata, pkg$data, pkg$resource_map) in the set_rights_and_access function, or include a hide-able code chunk for this code explicitly so that it's all in one place.

• Proper code is pkg <- get_package(d1c@mn, packageId). This is easy, so maybe just include it all together so it's easy to follow/copy

[dvirlar2]

There's already a callback to the Reference Guide section on how to get all pids of a package, but I don't think it's obvious that future interns or Data Coordinators should look at that link. Might be better to write something like:

Make sure to retrieve all pids associated with the package with the code below. Additional information can be found here.
pkg <- get_package(d1c@mn, packageId)

This would, ideally, go between setting the subject and set_rights_and_access() code blocks.