cut lines when trying to read "inbox" from the command-line client

I received an email yesterday saying that I had an encrypted message awaiting in my inbox. The `keybase chat --help` document is not very helpful in knowing how to read inbox messages, but `keybase chat ls` apparently tries to do the job:

```
$ keybase chat ls
[1] * chris [chris 2d] hey @gasche, you provisioned Keybase for linux (devi...
​
This is easily fixed. Our key hasn't changed, but we...
​
If you're not on a debian/ubuntu linux, you shouldn'...
```

This is the integral output. Notice that the lines are cut with `...` added. I have found no way to read the message, that is to have the lines *not* be cut:

1.`keybase chat ls | less` or `keybase chat ls | cat` does not do the job, while they should work.
2. There is no documentation about line length limits in `keybase chat --help` or anywere in the documentation that I could find. No documentation online either.
3. This is terrible, terrible UI design, who would even want the content to be *cut* by default? Line wrapping makes sense, but I don't see any reason for cutting lines.

Start with the `keybase chat --help` entry point and reproduce the behavior using `keybase chat ls`, both interactively and when piped to `less` or `cat`. Trace how inbox lines are formatted and determine how output should behave without truncation; done means messages remain readable in both terminal and piped output.

Written by the indexing model from the issue text.