When feeding a multi-line string to parse_text(), the resulting nodes

were a paragraph of paragraphs, which doesn't properly convert to HTML.

It ends up resulting in some extra blank paragraphs, messing with

spacing.
This changes parse_text() to default to returning the child elements

that were created, rather than the containing node. For those uses where

we do want a containing node returned, we can still do so, but it's now

optional.
This fixes some odd spacing issues I've noticed for a while in our API

docs in field descriptions.

Browsed through the docs. Paragraphs were still intact, as were the

nodes that needed the specific wrapping element. Field definitions that

had extra empty paragraphs were fixed.