Make the createItems linking phase a bit more resilient to exceptions.
Rewording of comments.
Address code review comments on 89086c3 (see https://github.com/JedWatson/keystone/pull/554#comments)
Use utils.plural when logging the updates warning count.
Merge pull request #554 from webteckie/master

Make createItems more resilient to crash exceptions
No 'New (List)' button w/ nocreate, fixes #563