Watch History

1. Add a query for watch history. Users should be able to query their own watch history and admins should be able to query all users.

2. Additionally, statistics on it which would return the number of watched episodes and movies for the specified user and time period, either in a "in the past X days" or "from X date to X date" query. This might be better as a separate query but I leave it up to you guys.

These would be part of the upcoming current streams dashboard on the frontend, and possibly for a "recently watched" section for a user's homepage.

Parameters would be optional user IDs (as an array) and a limit with a sane default, otherwise it returns all users play history. Sorting by timestamp in either direction and paging would be good.