Improved (alphabetical) sorting within custom groups/playlists

[giejay]

Is your feature request related to a problem? Please describe.
It's not very visible what exactly is added to a custom group within a custom playlist and what the order of that channel within the custom group is. Also the sorting of channels in a (custom) group is a bit of a pain with the html input of the "order" column.

Describe the solution you'd like
The ability to more easily see what channels are added to groups and being able to sort them easier.
So, from the "groups" tab in the custom playlist, also see which channels are below that group, and being able to drag them to sort for example.

A handlebar, with which you can drag channels, before the X icon would already be a great help for example. And even better if this handlebar would be included in the groups tab, when channels would be shown below these groups. The index of the "replaced" channel would then be increased by one (or minus 1 when dragging down;))

Finally, it would be really great if the channels could simply be alphabetically ordered with one click (inside a custom group).

Describe alternatives you've considered
Currently I'm using the channels overview page inside a custom playlist, and then sort on group and edit the channels order one by one by inputting a number.

[sparkison]

This has been requested before, and the nesting/drag and drop gets tricky. I'll keep it as a nice to have, but going to move this to the discussions for now.