windows add workon support code example

Example 1: virtualwrapper

$ pip install virtualenvwrapper
...
$ export WORKON_HOME=~/Envs
$ mkdir -p $WORKON_HOME
$ source /usr/local/bin/virtualenvwrapper.sh
$ mkvirtualenv env1
Installing
setuptools..........................................
....................................................
....................................................
...............................done.
virtualenvwrapper.user_scripts Creating /Users/dhellmann/Envs/env1/bin/predeactivate
virtualenvwrapper.user_scripts Creating /Users/dhellmann/Envs/env1/bin/postdeactivate
virtualenvwrapper.user_scripts Creating /Users/dhellmann/Envs/env1/bin/preactivate
virtualenvwrapper.user_scripts Creating /Users/dhellmann/Envs/env1/bin/postactivate  New python executable in env1/bin/python
(env1)$ ls $WORKON_HOME
env1 hook.log

Example 2: virtualenvwrapper-win cannot workon powershell

function workon ($env) {
        & $env:WORKON_HOME\$env\Scripts\activate.ps1
}