Validation messages typos

- Fixed typos in English shared validations.
Consistent authorized redirection in controllers

- Added missing redirection changes to scaffolding templates.
Removal of duplicated code in role provider

- Removed duplicated "need authorization logic in role provider
authorization methods.
Exception on missing controller action

- Added more specific exception then controller action is not found for
providing authorization information.
Account username trimming

- Added both side trimming for newly created or edited accounts.