Add support for multiple workspaces

[j6k4m8]

This adds (backwards-semi-incompatible) support for multi-workspace:

Set up a new workspaces lookup in your config:

{
    "workspaces": {
        "work": {
            "slack_token": "xoxp..."
        },
        "friends": {
            "slack_token": "xoxp...",
            "notify": "all"
        },
    },
    // All existing configs
}

Then invoke with:

slack-term -workspace friends

All options (except for workspaces itself) can also be specified in each workspace config, except for emoji which I'm not sure how to check for in this implementation. (Thoughts welcome!)

If you do not specify a -workspace flag, the first one (alphabetically) will be selected. This is nice for invoking in cases where users have only a single workspace, and is a sane default otherwise.

See #46 for earlier discussion.

[frzifus]

👍

[aakropotkin]

I just installed this it's fantastic! Thank you!
The only suggestion I would make is to make the "workspaces" object optional for backwards compatibility. If this got merged into master and folks updated, they would crash and need to head over to github to learn about the change.
If you still accept the old tag you don't break folks configs, or alternatively have it print a descriptive message if "workspaces" is missing.

Thank you for your hard work this is a fantastic addition!

A keymap to change workspaces is a logical extension, I might take a crack at that.

I wrapped mine is a zsh script to prompt for the workspace:

function slack-term() {
  if [[ $# -lt 1 ]]; then
    read "workspace?Which workspace: (`jq -r '.workspaces | keys | @csv' $HOME/.slack-term | sed 's/"//g' | sed 's/,/\|/g'`) ? "
  else
    workspace=${1}
  fi
  command slack-term -workspace $workspace
}

Ex: Which workspace: (work|friends) ?

[j6k4m8]

@alexameen roger that! I'll try to get a fix for this in shortly.

@erroneousboat would you be interested in a slack-term list-workspaces command?

[jpbruinsslot]

At the moment I don't see the advantage of this, instead of using multiple configuration files. Only that you have one config file.

[j6k4m8]

@erroneousboat The advantage is that you can share settings across workspaces instead of needing to edit each file independently. But happy to leave this as a fork and close the PR if you prefer!

[gshpychka]

@erroneousboat Do you still believe that copy-pasting configs between workspaces, and having to edit them in five places every time you need to change something is a good idea?