Introduces logic to detect and enforce centrally managed email settings. When managed, email options are displayed as read-only and cannot be changed by users; attempts to save changes are blocked with a notice. The email options view now conditionally renders a read-only summary and test email form if management is enabled.
Introduces open registration settings in the options area, allowing administrators to enable or disable public user signup. Adds a registration options page, updates sidebar navigation, and implements a public signup form and controller logic. Also refines user model to ensure correct data types for user fields and updates language strings for registration. The login page now links to signup when open registration is enabled.
This commit does a couple of things
- Creates OptionsLib which stores the 'Options' within the CI config system prefixed with "options_"
- Loads the OptionsLib automatically
- Adds function to OptionsLib for selecting the active stylesheet.
- Adds function to get an option_value that isn't automatically loaded.
