tlparse intructions wrong?

I did what was in the README:
```
TORCH_TRACE=/tmp/my_traced_log_dir python foo.py
tlparse /tmp/my_traced_log_dir -o tl_out/
```

The second command errored with
```
Error: /tmp/my_traced_log_dir is not a file
```

Needing to find the .log file inside the tempdir is a bit unfriendly