Migration improvements

[ellneal]

I've made a couple of changes here:

Make sure that couchrest-hash is set on created design docs during migrations

The current behaviour is that running migrate on a new design doc twice would result in :created and then :migrated, performing the view indexing both times. With this change the results of that example are now :created and then :no_change.

Add support for nested proxies in CouchRest::Model::Utils

class Company < CouchRest::Model::Base
  proxy_database_method :id
  proxy_for :clients
  property :name
  design { view :by_name }
end

class Client < CouchRest::Model::Base
  proxied_by :company
  proxy_database_method :id
  proxy_for :invoices
  property :name
  design { view :by_name }
end

class Invoice < CouchRest::Model::Base
  proxied_by :client
  property :date
  design { view :by_date }
end

Currently, given the above proxying hierarchy, the migration utility functions (and subsequently the rake tasks) would fail because they only traversed one level of proxying. The changes I've made allow the migration to iterate through all the companies, and then all the clients within each company and update the invoice design docs (it's recursive so this could be taken to even more ridiculous depths than I'm using it for). And while I was in there I wrote some more tests for the basic functionality.

---

Sorry to be continuously bombarding you with pull requests, I just keep hitting edge-cases 😄

[samlown]

Looks awesome! Always felt that there weren't enough tests on the migration stuff! Thanks.