anchor.diff:  resource_exists() -> 'true'.
   resource_exists(_) -> 'true'.
   resource_exists(?CARRIERS,_) -> 'true';
  +resource_exists(?CUSTOMERS,_) -> 'true';
  +resource_exists(?SERVICE_PLANS,_) -> 'true';
   resource_exists(?MODB,_) -> 'true'.
   resource_exists(?CARRIERS,_,_) -> 'true';
   resource_exists(?MODB,_,?ATTACHMENT) -> 'true'.
  
positive.code: validate_onbill(Context, ?CARRIERS, Id, ?HTTP_GET) ->
      read_onbill(<<"carrier.", (kz_util:to_binary(Id))/binary>>, Context);
  validate_onbill(Context, ?CARRIERS, Id, ?HTTP_POST) ->
      save_onbill(build_carrier_doc_id(Id, Context), Context).
  
  validate_onbill(Context,?CARRIERS, Id, AttachmentId, ?HTTP_GET) ->
      load_carrier_attachment(Context, build_carrier_doc_id(Id, Context), <<Id/binary, "_", AttachmentId/binary, ".tpl">>);
  
negative.code: -define(ATTACHMENT, <<"attachment">>).
  -define(GENERATE, <<"generate">>).
  -define(CARRIERS, <<"carriers">>).
  -define(CUSTOMERS, <<"customers">>).
  -define(SERVICE_PLANS, <<"onbill_service_plans">>).
  -define(MODB, <<"onbills_modb">>).
  -define(RESELLER_VARIABLES, <<"onbill_reseller_variables">>).
  -define(NOTIFICATION_MIME_TYPES, [{<<"text">>, <<"html">>}
  