Added ability to change volume level with scroll wheel

[TDDR]

---

Added ability to change volume level with scroll wheel

Pull Request Type
Please select what type of pull request this is:

• Bugfix
• Feature Implementation

Related issue
Fixes #573

Description
As the title suggests, I was finally able to figure out how to enable volume scroll on hover. Now, when the user hovers over the volume panel the user can change the volume with a wheel scroll.

Desktop (please complete the following information):

• OS: Windows 10
• OS Version: 1909
• FreeTube version: 0.9

Additional context
There is one thing that I found in testing that I am unsure if you would consider it a bug or a feature. If the user clicks on the mute button, that locks out the ability to wheel scroll the volume back on. The user must manually click the mute button again to unmute.

[Svallinn]

Apparently, the mouse wheel still changes the volume while the video is muted.
e.g. if you are at 50% volume, mute, scroll up and unmute, you can put it at 100% and can easily have it blasting your ears accidentally.
This is merely a suggestion, but try adding a condition that prevents the mouse wheel from modifying the sound if the video is muted.

[GilgusMaximus]

But that depends on the user. I would expect the program to do that honestly.

[Svallinn]

Yeah, I guess it does differ from person to person, it's probably fine as it is.
I'll leave it up to TDDR to make that call.

[TDDR]

Thanks for catching that Synkky. That should be an easy enough condition to check for, but I think I'll leave it up to PrestonN to decide if it's a bug or a feature.

[PrestonN]

Apologies for the delayed response on this.

I would say that if the volume is muted and the user scrolls up, this should unmute the volume and set it to 0.05 (whatever is the lowest increment). Ideally it shouldn't be changing the volume in the background where the user doesn't understand what's being changed. This should be fairly simple to implement.

Let me know if you have any questions about it.

[TDDR]

Finished those amendments. Let me know if it's up to par!

[TDDR]

Sorry, I messed up my local branches. I'm gonna re-submit a PR for this.