Include cumf output path when running rose-ana comparisons using cumf

A user has requested that when rose-ana runs a cumf comparison, the output directory from that comparison is included in the output, so they can trace what exactly was run and investigate problems in more detail without having to rerun the command.

This changes cumf so it produces output along the lines of:
```
[FAIL] Files differ: /path/to/my_output.dat c.f. /path/to/kgo.dat
[FAIL]    (/path/to/cumf_out_UW8n) 
```

so you can find the information produced by the comparison in ```/path/to/cumf_out_UW8n```.