Deconflate organization/conference IDs in role versions

Resolves failing test spec/features/versions_spec.rb:321

Partially reverts 81853d1ef9

db/migrate/20200331214534_add_organization_to_versions.rb

@@ -0,0 +1,37 @@
+class AddOrganizationToVersions < ActiveRecord::Migration[5.2]
+  def up
+    add_reference :versions, :organization
+    deconflate
+    PaperTrail::Version.reset_column_information
+  end
+
+  def down
+    conflate
+    remove_reference :versions, :organization
+    PaperTrail::Version.reset_column_information
+  end
+
+  private
+
+  def conflate
+    say 'conflate'
+
+    PaperTrail::Version.where.not(organization_id: nil).each do |version|
+      version.update conference_id: version.organization_id
+    end
+  end
+
+  def deconflate
+    say 'deconflate'
+
+    PaperTrail::Version.where.not(conference_id: nil).where(item_type: %(Role UsersRole)).each do |version|
+      id = version.conference_id
+
+      if Organization.exists?(id)
+        raise "version #{version.id} conflates organization #{id} with conference #{id}" if Conference.exists?(id)
+
+        version.update conference_id: nil, organization_id: id
+      end
+    end
+  end
+end