Bug Fix: Removed redundant virtualenvwrapper line

This line:
`source /usr/local/bin/virtualenvwrapper.sh`

is unnessisary because of these two lines:
```
[[ -a /usr/local/share/python/virtualenvwrapper.sh ]] && source /usr/local/share/python/virtualenvwrapper.sh
[[ -a /usr/local/bin/virtualenvwrapper.sh ]] && source /usr/local/bin/virtualenvwrapper.sh
```

This was causing an error because in my specific instance my
`virtualenvwrapper.sh` file only existed under `/usr/local/share`