Add creation time for tags

Currently, you see something like this when you list a directory:

```
drwxr-xr-x 0 root root 0 Dec 31  1969 ../../from:archive.org/
```

it'd be nice if you could see something more like this:

```
drwxr-xr-x 0 mwatts15 mwatts15 0 Oct 31  2015 ../../from:archive.org/
```
