Wrong use of "new" episode actions

[stefankoegl]

Detlef currently sends a "new" episode action for every new episode it detects. As actions are shared among devices and are meant to semantically "overwrite" each other, this does not reflect the intended meaning. A "new" action should be used to mark an episode as new again, eg after it has been played. As there is (currently) no such functionality in detlef, it should not send such actions at all.