All tags are put on a line by themselves to help with visual
diffing. Apparently this extra cosmetic whitespace causes problems inside p
tags for ppl who want to use `white-space: pre`. Not much hurt for visual
diffing in removing cosmetic whitespace for just p tags and can't think of
anything that would break because of this right now. So let's do it and wait
for things to break.
I didn't consider that all newlines in the pre block will be printed and we
thus shouldn't wrap html that has it's tags on separate lines (i.e. contains
superfluous newlines) - wrapping in a div less accurately represents
org-html-export but it provides the same information and gives us more freedom
in the return value of HighlightCodeBlock as well as allowing us to keep the
html tags on new lines (consistency).
... hopefully correctly
This will hopefully improve ease of developing (more granular test results) and
prepares us for adding example org->html renders for gh-pages
