Clean up plugin READMEs and a few plugins

- fasd
- history
- mercurial
- pylint
- repo
- yii2

plugins/fbterm/README.md

@@ -3,7 +3,8 @@
 This plugin automatically starts [fbterm](https://github.com/zhangyuanwei/fbterm)
 if on a real TTY (`/dev/tty*`).
 
-To use it, add fbterm to the plugins array of your zshrc file:
-```
+To use it, add `fbterm` to the plugins array of your zshrc file:
+
+```zsh
 plugins=(... fbterm)
 ```