Add notes support for all models that support notes

[whitej6]

Improve notes support

Current State

API does not have a "notes" attr in the return payload and only returns "notes_url" as a link to a list view for all notes that apply to the current instance.

Proposal

Provide ".notes" on any model that provides notes and the attribute would be an pynautobot.core.endpoint.Endpoint to allow for create update and delete operations scoped to just the current model instance

Example desired outcome

dev = py_nb.dcim.devices.get(name="foo")
count(dev.notes.all()) # return N notes created on a device named foo
note = dev.notes.create(note="bar")
note.note="baz"
note.save()

count(dev.notes.all()) # return being N+1 of previous count