Moves ORM specific code to lib/impressionist/:orm/models. Adds mongo_mapper models.

Adds config/initializers/impression.rb file on install.

lib/generators/impressionist_generator.rb

@@ -2,6 +2,11 @@ module Impressionist
   module Generators
     class ImpressionistGenerator < Rails::Generators::Base
       hook_for :orm
+      source_root File.expand_path('../templates', __FILE__)
+
+      def copy_config_file
+        template 'impression.rb', 'config/initializers/impression.rb'
+      end
     end
   end
 end

lib/generators/mongo_mapper/impressionist_generator.rb

@@ -0,0 +1,8 @@
+module MongoMapper
+  module Generators
+    class ImpressionistGenerator < Rails::Generators::Base
+      # Empty for now, need it for generating the config file without
+      # triggering other ORM's generators.
+    end
+  end
+end

lib/generators/templates/impression.rb

@@ -0,0 +1,5 @@
+# Use this hook to configure impressionist parameters
+Impressionist.setup do |config|
+  # Define ORM. Could be :active_record (default) and :mongo_mapper
+  # config.orm = :active_record
+end