robbyrussell/oh-my-zsh — pull request #3293 by javajax (2014-11-06 00:33:41+00:00)
Title: This adds two functions to modify your PATH.

Both functions check to see if the directories that will be inserted
into your PATH are currently on the system. This is good for having
one zshrc file and deploying it to myltiple enviroments.

example:
```
prepend_path "${HOME}/bin"
postpend_path "/usr/local/bin/heroku"
```