Add task to rebuild CookbookVersion dependencies

The data migration erroneously migrated version constraints of the form
`OPERATOR MAJOR.MINOR` as `OPERATOR MAJOR.MINOR.0`. To fix this, we add
a worker which corrects that mistake for a single CookbookVersion, and a
rake task which can seed it with jobs.
Increase pool size in development to support Sidekiq
Merge pull request #580 from opscode/reprocess-imported-archives

Reprocess imported archives