[Doppins] Upgrade dependency slack-client to 2.0.4

[doppins-bot]

Hi!

A new version was just released of slack-client, so Doppins has upgraded your project's dependency ranges.

Make sure that it doesn't break anything, and happy merging! :shipit:

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Upgraded slack-client from 1.5.0 to 2.0.3

Changelog:

Version 2.0.3

• The RTM AUTHENTICATED event now also emits the rtm.start payload
• Fixes the way that loggers are instantiated and used, so that the JSDoc for opts.logger is correct

  Version 2.0.2

• Adds coveralls to the repo, to track code coverage and display a badge in the README
• Updates the disconnect function on the RTM client to support both an error message and a code or reason for the disconnect, e.g. account_inactive
• Updates the message-handlers for team_xxx events to set the team back to the data-store once changes are made

  Version 2.0.1

• Updates to ws@1.0.1
• Fixes a bad variable name in example-web-client

  Version 2.0.0

Refactors the library to javascript, adds a lot of tests and restructures it to improve maintainability and extend functionality.

• Creates two separate clients:
  • RTM; manages connection to Slack's RTM API, including reconnects
  • Web; provideas a callback interface to all of Slack's Web API endpoints
• Moves the memory data store implementation off the clients and into its own class
• Uncouples the model objects from the clients; model functions to send messages to channels etc are now accessed via the web and RTM client
• Moves the transport layer (websockets and HTTP) to a pluggable model, so that complex transports (through request proxies etc) can be handled
• Adds test coverage on most core functionality in the library

[doppins-bot]

An additional new version was just released of slack-client, so we've added an extra commit upgrading your range to 2.0.4.

Hope that's alright! — Doppins