Fix some more style issues with rendered Markdown text.
This fixes the lists to wrap correctly. We're back to native bullet

points, but now things line up correctly. Nested lists also now work,

whereas before they were flat.
The pre-wrap white-space mode has been turned off for all non-code

elements, fixing some other spacing problems.

Tested in Firefox and Chrome. Lists align properly, match up to the

source text well, and don't have extra blank lines after nested lists.