Correct typo in method name "factoral" -> "factorial".  It's experimental code, so users will have to migrate.  Better now than later.  Fixes #7128
Correct typo in method name "factoral" -> "factorial".  It's experimental code, so users will have to migrate.  Better now than later.  Fixes #7128

git-svn-id: ee6e786acc44c9cca5ee17c71a5576c45c210361@14368 560b804f-0ae3-0310-86f3-f6aa0a117693

redaktor/deliteful