consistent whitespace across the .rst docs, some minor corrections

Nothing really here, feel free to reject, I just love to read docs in my vim that are < 80 cols wide.

I found a couple of minor ~actual edits to make.

`queues` is undefined: https://github.com/twilio/twilio-python/blob/master/docs/usage/queues.rst#listing-queues

"The :class:`Recordings` resource allows you to delete unnecessary recordings" is erroneously repeated here: https://github.com/twilio/twilio-python/blob/master/docs/usage/recordings.rst#accessing-related-transcptions

There may be other small things to fish out in lieu of taking this whole commit.