Support for groups

[fabiospampinato]

We should add support for groups, this would allow us to group some terminals together. The benefits are better organization and the ability to run more than one terminal, but not all of them, at the same time.

The quickpick would look something similar to this (Gif taken from Projects+):

[tnrich]

This would be an awesome feature!

[zirkelc]

Would be a great feature for teams working in one mono-repository.

[gigamesh]

Would love support for groups!

[cssinate]

In order to not break existing configs, I'd propose a key like

{
  "name": "This Terminal"
  "runWith": ["Other Terminal 1", "OT2"]
}

If This Terminal is onlySingle: false then we check the onlySingle status of Other Terminal 1 and OT2 and if one of the terminals inside runWith also has onlySingle: false then we can safely ignore it when Terminals: Run is executed. We then ensure we run them if This Terminal is launched with Terminals: Run Single.

[cssinate]

The workaround I came up with requires adding a keybinding. See here: #82 (comment)