adding to channels with wildcard

[umlaeute]

it would be great if it was possible to extend the ChannelsAddedTo syntax to allow wildcards.

as in the following, where the user would get added to bugs, developers, devops, devsecops, devices and devilish

"Actions" : [
{
  "ActionType": "button",
  "ActionDisplayName": "Developer",
  "ActionName": "developer-action",
  "ChannelsAddedTo": ["bugs", "dev*"],
  "ActionSuccessfulMessage": [
    "### Awesome! I have added you to the developer channels:"
  ]
},

[jrepe]

hey, mind if I have a go at this one?

[jrepe]

I've a question, I have roughly implemented this using SearchChannels(teamId, term string) ([]*model.Channel, *model.AppError), however it would appear I'm not able to get private channels through this approach.