Clean up plugin READMEs and a few plugins

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

plugins/last-working-dir/README.md

@@ -6,4 +6,10 @@ for new shells, unless:
 - The plugin is already loaded.
 - The current `$PWD` is not `$HOME`.
 
-Adds `lwd` function to jump to the last working directory.
+Also adds `lwd` function to jump to the last working directory.
+
+To use it, add `last-working-dir` to the plugins array in your zshrc file:
+
+```zsh
+plugins=(... last-working-dir)
+```