Make help text plain when piped to terminal in aws2

I would like for the text output of aws2 to be plain text when it is not sent to tty, i.e. it's going to a pipe or file. If I do this:

```
[lousyd ~]# /usr/local/bin/aws2 help | grep -- '--query'
--query (string)
```

But if I do this:

```
[lousyd ~]# /usr/local/bin/aws2 help | grep -- '^\s\+--query'
```

...nothing. That's because:

```
[lousyd ~]# /usr/local/bin/aws2 help | grep -- '--query' | cat -A
^[[1m--query ^[[22m(string)$
```

There's a bunch of other junk in there meant to make the output look pretty in the terminal. But that junk just gets in the way of standard text processing.

Please either make help output plain text when output is not to a tty, or just output plain text all of the time.