Selection mode for 'Add to history'

**Is your feature request related to a usage problem (not a bug)? Please describe.**
Usage problem additional to #357
When starting fresh with FreeTube or finding a new channel all older videos from newly subscribed channels will flood the subscription section.
Two possible scenarios where this is inconvenient:
- I've already watched most of these older videos and/or
- I won't catch up on all the older videos and am only interested in newer content

which is why I'm very hesitant to subscribe to new channels right now.

**Describe the solution you'd like to see implemented**
Add the possibility to mark videos as watched by their upload dates for a specified time frame/older than XY
- via a pop-up menu (embedded in the channel view (/additionally when subscribing))
- or by using a select option with something like CTRL+LMouse and +Shift for ranges (which could also later be used for functions like playlists).

**Describe alternatives you've considered**
In "Subscription" only show uploads from newly subscribed channels with upload dates after they have been added. Though I'm not the biggest fan of that myself and not sure if that would interfere/create unnecessary confusion with the "Hide Videos on Watch" setting (i.e. when accidentally unsubscribing or wanting to add older videos to the Subscription page by removing them from history). I was pretty sure there was an issue already discussing this alternative but for the life of me I can't find it anymore.