Print only the relative path

Let's say I call magic on a folder

```
magic ../ooc/ooc-kean
```

I would like to be able to have it print only the relative path to the folder, not the absolute path. So instead of 

```
/home/dhesselbom/versioned/ooc/ooc-kean/source/math/Quaternion.ooc
```

print

```
source/math/Quaternion.ooc
```

or make this behavior optional, at least.
