Add an option to automatically add an Anime to "Watching"

[m4tx]

Tundra only scrobbles an anime when the user has it marked as "Watching" or "Plan to watch". It would be nice to add an option to recognize it even when it hasn't been marked as such before. It should be non-invasive though, so the user isn't prompted each time he/she watched a random tv series (infobar in the app UI?)