Fix string in heading and breadcrumbs

app/models/error_template.rb

@@ -1,4 +1,8 @@
 class ErrorTemplate < ActiveRecord::Base
   belongs_to :execution_environment
   has_and_belongs_to_many :error_template_attributes
+
+  def to_s
+    "#{id} [#{name}]"
+  end
 end