Mark episodes as watched: improvements

[TRtomasz]

Description Following things can be fixed and improved.

• [ ] Remove notification about new episode from the Board and from the details page(yellow font) when user marks it as watched or when he actually starts to play it.

• [ ] When user selects whole Series as watched, marks every episode as watched, or show new Window where he can select from the Seasons/Episodes list

• [ ] Stremio should notify(event,trigger) "integration" add-ons like trakt or any other add-on of that kind when user marks movie as watched.

• [ ] Stremio should marks movies or episodes as watched after user has watched some part of the movie. Right now it works a little randomly. It can be additional setting or arbitrary % value.

Screenshots to 1st point