#286913 by hunmonk: schema shows typo for unique index.  looks like the result is still correct in the database, so i don't think a db update is necessary.

Per-recent 6.x API change, make sure all child menu items have explicitly declared access definitions.

user_edit form renamed to user_profile_form. %user -> %user_category for menu item altering. fix notice.

capitalization fixes in help text. fix undefined var. use constant for anon user rid. fix submit handler in settings forms.

use db_placeholders() where appropriate. while the old code was not insecure, this approach is cleaner and safer in the long run.

change protection messages to status messages instead of error messages for account edit page and new account creation.

only check  user/X/edit fields for protections if they exist.  clean up the display of current protections so that only the fields being actively protected are displayed. Eliminate password fields if protected, rather than displaying disabled fields.

added 'change own e-mail' and 'change own password' perms for the module.  these mirror the 'change own username' perm in core and allow admins role-based control over these fields as well.  when a user is editing their own account, only these perms are checked for the email and password protection settings.