requests/problems: channel editing struggles

[M0ahgra]

some problems:

• when transfering the data from 1 channel to another, the data has to be moved manually.
• channels wont always be ordered the way you want, rearranging channels requires manual copying.
• cant remove channels inbetween other channels because channels are only added or removed from top to bottom.

suggestions:

• allow channels to be rearranged by moving them around (similar to how patterns can be copied and moved around, maybe even give channels names or numbers like patterns have?).
• allow channels to be added anywhere (not terribly necessary if channels can be rearranged easily).

some other things:

• add soloing option for channels (like how audacity channels have mute and solo, and not just mute).
• add saving of channel mutes with beepbox json file.
• cant select more than one of certain things (such as instruments), thus you cant copy and move such things as flexibly as patterns.

[johnnesky]

For some of these requests, you're in luck!

Ctrl + up/down arrows moves the selected channel up or down, trading places with adjacent channels.

Ctrl + Enter inserts a new channel immediately underneath the selected one, and Ctrl + backspace removes the current channel.

The S key will solo the selected channels. (But it's not a separate setting from muting the other channels.)

Some of these options are also in the edit menu.