Fix indentation and newlines in generated engine

railties/lib/rails/generators/named_base.rb

@@ -42,7 +42,7 @@ def indent(content, multiplier = 2)
         end
 
         def wrap_with_namespace(content)
-          content = indent(content)
+          content = indent(content).chomp
           "module #{namespace.name}\n#{content}\nend\n"
         end
 

railties/lib/rails/generators/rails/plugin_new/templates/lib/%name%/engine.rb

 module <%= camelized %>
   class Engine < Rails::Engine
 <% if mountable? -%>
-      isolate_namespace <%= camelized %>
+    isolate_namespace <%= camelized %>
 <% end -%>
   end
 end