Parse prune output.

def _xfs_prune_output(out, uuid):
    '''
    Parse prune output.
    '''
    data = {}
    cnt = []
    cutpoint = False
    for line in [l.strip() for l in out.split("\n") if l]:
        if line.startswith("-"):
            if cutpoint:
                break
            else:
                cutpoint = True
                continue

        if cutpoint:
            cnt.append(line)

    for kset in [e for e in cnt[1:] if ':' in e]:
        key, val = [t.strip() for t in kset.split(":", 1)]
        data[key.lower().replace(" ", "_")] = val

    return data.get('uuid') == uuid and data or {}