update the awk update to be a bit more readible

This just makes the `showmarks` output a bit prettier: 
```
 berndrennebeck@brenn-mbp: ~/Development/zshmarks on git:feature-showmarks-output o [21:57:34]
$ showmarks
dev                 /Users/berndrennebeck/Development
899projects         /Users/berndrennebeck/Development/899/Projects
projects            /Users/berndrennebeck/Development/Projects