Skip 3694 warnings on trivial resource cloning

Turns the 3694 warning into a debug message if the prior resource is
identical to the current resource.  Suggestion for opscode/chef-rfc#76
`source_line`, `cookbook_name`, and `recipe_name` will all be unique though.  `params` is a hack for definitions that doesn't seem to matter.  `elapsed_time`  also doesn't matter and helps with the case where someone has forced a resource to run at compile time.