Rename DB field identifiers.status to identifiers.active

Rename DB field identifiers.status to identifiers.active

This better reflects what is the meaning of the value.

If you need to manually create the table, use the following command,
not the one from the previous commit.

    CREATE TABLE if not exists identifiers (
        `userid` varchar ( 24 ) NOT NULL,
        `id` varchar ( 24 ) PRIMARY KEY NOT NULL,
        `name` varchar ( 24 ),
        `active` INTEGER NOT NULL DEFAULT 1,
        FOREIGN KEY(`userid`) REFERENCES `users`(`id`)
    );