Debug messages show scrubbed backtraces
Cookbook Dependency imports can be marked as read-only

Ordinarily such an import would not yield any ActiveRecord objects if
the destination cookbook version already had its dependencies imported.
If an import is read-only it will yield the same ActiveRecord objects as
it would if the destination cookbook version had not had its
dependencies imported, but with the catch that the yielded objects are
read-only.
Don't abort the import if all that's wrong is a missing README

READMEs were not always required, so there are a good number of
cookbooks missing them.
Add task to gradually verify that all dependencies/READMEs got imported
Run followup actions outside of the main transaction
Merge pull request #10 from gofullstack/verify-cookbook-version-tarball-migration

Verify cookbook version tarball migration