(#9051) Make generic tagging imported resource origins.

When StoreConfigs was tied to rails, parser resources were tagged with a
rails_id to allow the code to determine if this was the same object we had
previously imported.

Now that we are making that generic, rename that to collector_id to make it
clear that it isn't so directly tied to the original purpose.

Signed-off-by: Daniel Pittman <daniel@puppetlabs.com>