Add functions_module.php core events to allow adjusting parameters for custom ACP, MCP, UCP modules

Identifier: core.modify_module_row_before
Identifier: core.modify_module_row_after
Location: includes/functions_module.php function list_modules().
Explanation: these events allow extensions to modify ACP, MCP, UCP custom modules display/list options (like adding extra URL parameters and so on).
Use case: For extensions which create custom modules.