"sp_helptext" command should output only the result (without "frame")

First of all, that's feature request.

When using `sp_helptext` command, it would be better not to print the "frame" (Example 1) where the output of the command is inside of.

Like this:
```
+-----------------------------------------------------------------------------------------------------------------------+
| Text |
|-----------------------------------------------------------------------------------------------------------------------|
| Content |
+-----------------------------------------------------------------------------------------------------------------------+
Commands completed successfully.

```

Especially when using `-Q` option.

That allow us to use mssql-cli in scripts context because the output would be more "parseable".