anchor.diff:  		Event :: {Type, Resource, Category},
   		Type :: create_bucket | delete_bucket | charge | depleted | accumulated
   				| create_product | delete_product | create_service | delete_service
  -				| create_offer | delete_offer | insert_gtt | delete_gtt | log_acct,
  -		Resource :: #bucket{} | #product{} | #service{} | #offer{}
  +				| create_offer | delete_offer | create_resource
  +				| insert_gtt | delete_gtt | log_acct,
  +		Resource :: #bucket{} | #product{} | #service{} | #offer{} | #resource{}
   				| {Table, #gtt{}} | [#adjustment{}] | [#acc_balance{}]
   				| ocs_log:acct_event(),
   		Table :: atom(),
  
positive.code: 			"LogicalResourceCreationNotification";
  		delete_gtt ->
  			"LogicalResourceRemoveNotification";
  		log_acct ->
  			"UsageCreationEvent"
  	end.
  
negative.code: 			ocs_rest_res_service:inventory(Resource);
  		resource ->
  			case Resource of
  				#resource{} ->
  					ocs_rest_res_resource:resource(Resource);
  				{Table, #gtt{num = Prefix, value = {Description, Rate, _}}} ->
  					ocs_rest_res_resource:gtt(atom_to_list(Table),
  							{Prefix, Description, Rate})
  