sqlite support

[532910]

Please add sql/sqlite.sql.

This one works for me, but I'm not sure if it's completely correct:

CREATE TABLE `auth_tokens` (
    `token` varchar(128) NOT NULL,
    `expires` datetime NOT NULL,
    `user_id` int(10)  NOT NULL,
    `user_name` varchar(128) NOT NULL,
    `user_pass` varchar(128) NOT NULL,
    `host` varchar(255) NOT NULL
);
CREATE INDEX token ON auth_tokens(token);

[twekkel]

Mostly okay and it will work. For some improvements please have a look at at https://github.com/mfreiholz/persistent_login/pull/60