Added class and os alternates

.oh-my-zsh/plugins/cask/README.md

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+# Cask plugin
+
+[Cask](https://github.com/cask/cask) is a project management tool for Emacs that helps
+automate the package development cycle; development, dependencies, testing, building,
+packaging and more.
+
+This plugin loads `cask` completion from non-standard locations, such as if installed
+via Homebrew or others. To enable it, add `cask` to your plugins array:
+
+```zsh
+plugins=(... cask)
+```
+
+Make sure you have the `cask` directory in your `$PATH` before loading Oh My Zsh,
+otherwise you'll get a "command not found" error.