Fix: README.

Author: dblock

README.md

@@ -1,13 +1,14 @@
 # Slack-Shellbot
 
-[![Add to Slack](https://platform.slack-edge.com/img/[email protected])](http://shell.playplay.io)
+[![Add to Slack](https://platform.slack-edge.com/img/add_to_slack.png)](http://shell.playplay.io)
+
 [![rubocop](https://github.com/slack-ruby/slack-shellbot/actions/workflows/rubocop.yml/badge.svg)](https://github.com/slack-ruby/slack-shellbot/actions/workflows/rubocop.yml)
 [![test](https://github.com/slack-ruby/slack-shellbot/actions/workflows/test.yml/badge.svg)](https://github.com/slack-ruby/slack-shellbot/actions/workflows/test.yml)
 [![Code Climate](https://codeclimate.com/github/slack-ruby/slack-shellbot/badges/gpa.svg)](https://codeclimate.com/github/slack-ruby/slack-shellbot)
 
 A shell bot for Slack. A demo is worth a thousand words.
 
-![](public/img/vi.gif)
+![](public/img/shell.gif)
 
 ## Contributing