Sidebar does not appear on third party docs

Its hardcoded with all endless help specific stuff, so it was just
horribly confusing on other help guides
[endlessm/eos-shell#4202]
Remove unused css from endless-custimizations.xsl.in

There was a lot of css that was not doing anything, removed it
[endlessm/eos-shell#4202]
Don't inject customs divs around the article body

We had a bunch of custom divs around the body content to imitate
the html structure we had for a short lived node implementation
of yelp.

We don't need them, and they were part of a gross web of divs and
css that was really hard to follow, and was leaving us with a
weird container around all our article content.

It also made it difficult to remove the sidebar, as the spacing
for the sidebar was hardcoded into a bunch of div margins.

With the new styling the only thing added through our custom
xslt is the sidebar. And the sidebar is simply put of the left with
float: left;
in the css.

This allows us remove the sidebar for third party docs and also
removed the ugly container around all article content
[endlessm/eos-shell#4202]
Simplify sidebar html

This was another mess of divs within divs that was way more
complicated than it needed to be

Simplified the elements as much as I could
[endlessm/eos-shell#4202]
Move article styling out of eos-help-center-style.css

We had some article styling in that file, but that belongs in our
separate article-style.css file.
[endlessm/eos-shell#4202]
Make the side list a ol instead of ul

Its an ordered list, so ol is more appropriate
[endlessm/eos-shell#4202]
Remove unused css utilities

I don't think font awesome was being used anywhere, not was
utilities.css.

Also some css files were included from other css files and also
included in through our xslt.

Did all the inclusion trough xslt to be consistent

[endlessm/eos-shell#4202]
Merge pull request #18 from endlessm/shell/4202

Shell/4202