When logging in to a new CentOS 7 machine COLUMNS has not been set before the theme is evaluated, causing the following error:
```shell
irongiant-mbp → ssh clayreimann@toren.ddns
Last login: Fri Jun 23 10:05:11 2017 from cpe-24-209-155-17.wi.res.rr.com
-bash: /1: syntax error: operand expected (error token is "/1")
-bash-4.2$
```
This fix is based on advice from https://stackoverflow.com/a/3601734
This change allows for the capture of the expanded prompt (rather than the raw `PS1`) so that
it is easier to maintain context when changing directories.
Fix is based on the comments from [this stackoverflow](http://stackoverflow.com/a/24006864)
Clay Reimann
Yuhao Wu
Phillip Aldridge
Phillip Aldridge