* The Conf class serves both as a means of importing and querying configuration information, as well as a source for default parameters when a configuration file does not specify a value.
* All public properties are configuration parameters that may be set by the server administrator. */
/** @var string The base server address (with scheme, host, port if necessary, and terminal slash) to connect to the server when performing feed updates using cURL */
/** @var string The user name to use when performing feed updates using cURL; if none is provided, a temporary name and password will be stored in the database (this is not compatible with pre-authentication) */
/** @var boolean Whether to allow the possibility of fetching full article contents using an item's URL. Whether fetching will actually happen is also governed by a per-feed setting */
/** @var string When to delete a feed from the database after all its subscriptions have been deleted, as an ISO 8601 duration (default: 24 hours; empty string for never)
/** @var string When to delete an unstarred article in the database after it has been marked read by all users, as an ISO 8601 duration (default: 7 days; empty string for never)
/** @var string When to delete an unstarred article in the database regardless of its read state, as an ISO 8601 duration (default: 21 days; empty string for never)
* The file must be a PHP script which return an array with keys that match the properties of the Conf class. Malformed files will throw an exception; unknown keys are silently ignored. Files may be imported is succession, though this is not currently used.
* @param string $file Full path and file name for the file to import */
* The input array must have keys that match the properties of the Conf class; unknown keys are silently ignored. Arrays may be imported is succession, though this is not currently used.
* @param mixed[] $arr Array of configuration parameters to export */