Fix NameError in seeds for production mode.

Move HetsInstance creation task to module.

Fix HetsInstance seeds.

fix seeds for HetsInstance creation in order to prevent an infinite recursion, we'll need to perform Sidekiq as it would in production — in other words, pushing jobs to redis instead of instantly performing them.

create hets-instance model This also includes creating the default localhost hets-instance during the seeds. Additionally some convenience methods for the version of a hets-instance have been created.