API - Basic API calls

This will become:
```php
        $queryArray = array(TABLE_PREFIX, $category_id);

        api_backbone((object)array(
            "request_type" => HTTP_DELETE,
            "access_level" => ADMIN_ACCESS_LEVEL,
            "query" => "DELETE FROM %scourses WHERE course_id = %d",
            "queryArray"  => $queryArray,
            "queryIDExistence" => "SELECT COUNT(*) FROM %scourses WHERE cat_id = %d",
            "queryIDExistenceArray" => $queryArray
        ));
```