Add NamingConventions::Field::FQN

Given

* a model with storage_name = ‘accounts’
* a property with name = ‘name’

returns ‘account_name’

This is useful for defining database schemas which need minimal
renaming for natural joins

lib/dm-core/support/naming_conventions.rb

@@ -78,6 +78,13 @@ def self.call(property)
  end
  end # module Underscored
 
+ module FQN
+ def self.call(property)
+ storage_name = property.model.storage_name(property.repository_name)
+ "#{DataMapper::Inflector.singularize(storage_name)}_#{property.name}"
+ end
+ end # module FQN
+
  module Yaml
  def self.call(property)
  "#{DataMapper::Inflector.pluralize(DataMapper::Inflector.underscore(property.name.to_s))}.yaml"