Show confirmation when profile changes are saved

When you save changes from editing your profile, it takes you back to the profile page but depending on what you changed, there may be no obvious indication that the changes have just been saved because some of the settings on your profile settings - e.g. timezone, custom profile fields - are not displayed on the profile page.

In recent testing, some students said they weren't confident that the changes had taken effect.

Proposed improvement: when you save profile changes it should use the standard Moodle notification system to add a notification which will then display as a dismissable banner on the next page, usually the profile page.

The notification text could be an generic existing text string if there is a suitable one, like 'Your changes have been saved' or something like that, or we could create a new string such as "Your profile settings have now been saved".