Create README.md for compleat plugin

plugins/compleat/README.md

+# compleat
+
+This plugin runs [bashcompinit](https://github.com/zsh-users/zsh/blob/master/Completion/bashcompinit) which will allow zsh to read bash completion specifications and functions.
+
+To use it add compleat to the plugins array in your zshrc file.
+ 
+ ```
+plugins=(... compleat)
+```
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